Damage rectanges.

* refs/remotes/tmux-openbsd/master:
  Add margins for WezTerm and ghostty, from Michael Grant.

.github/workflows/regress.yml

@@ -27,10 +27,10 @@ jobs:
             runner: ubuntu-24.04
             make: make
             configure: --enable-utf8proc --enable-asan
-          #- name: ubuntu-24.04-arm64
-          #  runner: ubuntu-24.04-arm
-          #  make: make
-          #  configure: --enable-utf8proc --enable-asan
+          - name: ubuntu-24.04-arm64
+            runner: ubuntu-24.04-arm
+            make: make
+            configure: --enable-utf8proc --enable-asan
           - name: macos-26-arm64
             runner: macos-26
             make: gmake
@@ -72,14 +72,14 @@ jobs:
 
       - name: build
         run: |
-         sh autogen.sh
+          sh autogen.sh
           ./configure ${{ matrix.configure }}
           ${{ matrix.make }} -j"$(getconf _NPROCESSORS_ONLN)"
 
       - name: test
         run: |
           cd regress
-          ${{ matrix.make }}
+          ${{ matrix.make }} -j"$(getconf _NPROCESSORS_ONLN)"
 
       - name: logs
         if: failure()

CHANGES

@@ -33,9 +33,7 @@ CHANGES FROM 3.7c TO 3.8
     line;
 
   - pane-border-status has top-floating and bottom-floating, and there are new
-    default bindings under C-b g for common move and resize operations;
-
-  - floating panes are unzoomed before creation to avoid a crash.
+    default bindings under C-b g for common move and resize operations.
 
 * Layout strings now use a JSON subset format which includes floating panes.
   The old format is still accepted; control mode clients receive old layouts
@@ -132,6 +130,8 @@ CHANGES FROM 3.7c TO 3.8
 
 * Add capture-pane -I to include the time each line entered history.
 
+* Various memory leak fixes from Heon Jeong.
+
 * Add a default C-b T binding to change the current pane title.
 
 * Menus now belong to the window, so appear on all clients.

Makefile.am

@@ -188,7 +188,6 @@ dist_tmux_SOURCES = \
 	options-table.c \
 	options.c \
 	paste.c \
-	popup.c \
 	proc.c \
 	prompt-history.c \
 	prompt.c \
@@ -258,7 +257,8 @@ check_PROGRAMS = \
 	fuzz/input-fuzzer \
 	fuzz/cmd-parse-fuzzer \
 	fuzz/format-fuzzer \
-	fuzz/style-fuzzer
+	fuzz/style-fuzzer \
+	fuzz/layout-fuzzer
 fuzz_input_fuzzer_LDFLAGS = $(FUZZING_LIBS)
 fuzz_input_fuzzer_LDADD = $(LDADD) $(tmux_OBJECTS)
 fuzz_cmd_parse_fuzzer_LDFLAGS = $(FUZZING_LIBS)
@@ -267,6 +267,8 @@ fuzz_format_fuzzer_LDFLAGS = $(FUZZING_LIBS)
 fuzz_format_fuzzer_LDADD = $(LDADD) $(tmux_OBJECTS)
 fuzz_style_fuzzer_LDFLAGS = $(FUZZING_LIBS)
 fuzz_style_fuzzer_LDADD = $(LDADD) $(tmux_OBJECTS)
+fuzz_layout_fuzzer_LDFLAGS = $(FUZZING_LIBS)
+fuzz_layout_fuzzer_LDADD = $(LDADD) $(tmux_OBJECTS)
 endif
 
 # Install tmux.1 in the right format.

SYNCING.md

@@ -35,7 +35,7 @@ The usual local layout is:
 ```sh
 cd /some/where/useful
 git clone https://github.com/tmux/tmux.git tmux-portable
-git clone https://github.com/ThomasAdam/tmux-obsd.git tmux-openbsd-cutover
+git clone https://github.com/tmux/tmux-openbsd-cutover.git tmux-openbsd-cutover
 ```
 
 The exact directory names do not matter, but the examples below use:
@@ -56,18 +56,19 @@ The cutover repository has three important branches:
 
 # Adding the OpenBSD remote to portable
 
-In the portable repository, add the cutover repository as a remote:
+In the portable repository, add the published cutover repository as a remote.
+This works regardless of which branch is checked out in a local cutover clone:
 
 ```sh
 cd /path/to/tmux-portable
-git remote add tmux-openbsd /path/to/tmux-openbsd-cutover
+git remote add tmux-openbsd https://github.com/tmux/tmux-openbsd-cutover.git
 git config remote.tmux-openbsd.tagOpt --no-tags
 ```
 
 If the remote already exists, update it instead:
 
 ```sh
-git remote set-url tmux-openbsd /path/to/tmux-openbsd-cutover
+git remote set-url tmux-openbsd https://github.com/tmux/tmux-openbsd-cutover.git
 git config remote.tmux-openbsd.tagOpt --no-tags
 ```
 
@@ -77,6 +78,32 @@ Fetch the cutover master branch explicitly:
 git fetch --no-tags tmux-openbsd master:refs/remotes/tmux-openbsd/master
 ```
 
+To merge unpublished changes from a local cutover clone instead, first ensure
+it has an up-to-date local `master` branch. A normal clone may check out
+`automation` and have only `origin/master`; fetching `master` from that clone
+will then fail with `couldn't find remote ref master`.
+
+With a clean cutover working tree:
+
+```sh
+cd /path/to/tmux-openbsd-cutover
+git fetch --no-tags origin
+git switch master
+git merge --ff-only origin/master
+```
+
+`git switch master` creates a tracking branch from `origin/master` if there is
+no local `master` yet. If the fast-forward fails, reconcile the local cutover
+changes before continuing; do not reset them away.
+
+Then, in portable, point the remote at that clone and fetch its local `master`:
+
+```sh
+cd /path/to/tmux-portable
+git remote set-url tmux-openbsd /path/to/tmux-openbsd-cutover
+git fetch --no-tags tmux-openbsd master:refs/remotes/tmux-openbsd/master
+```
+
 # Automated syncing
 
 The normal sync is performed by the GitHub Actions workflow in the
@@ -99,7 +126,9 @@ OpenBSD changes.
 If the workflow fails while merging into portable, do the merge locally and
 push the result.
 
-Start from an up-to-date portable master:
+Start with a clean working tree and an up-to-date portable master. If a merge
+is already in progress, skip to resolving conflicts, or abort it before
+starting again:
 
 ```sh
 cd /path/to/tmux-portable
@@ -108,10 +137,15 @@ git checkout master
 git pull --ff-only origin master
 ```
 
-Fetch the cutover branch:
+Fetch the published cutover branch. Update an existing remote as well, since
+it may point at a local clone without a `master` branch or with a stale one:
 
 ```sh
-git remote add tmux-openbsd /path/to/tmux-openbsd-cutover 2>/dev/null || true
+if git remote get-url tmux-openbsd >/dev/null 2>&1; then
+    git remote set-url tmux-openbsd https://github.com/tmux/tmux-openbsd-cutover.git
+else
+    git remote add tmux-openbsd https://github.com/tmux/tmux-openbsd-cutover.git
+fi
 git config remote.tmux-openbsd.tagOpt --no-tags
 git fetch --no-tags tmux-openbsd master:refs/remotes/tmux-openbsd/master
 ```
@@ -122,7 +156,22 @@ Merge it:
 git merge --no-ff --log refs/remotes/tmux-openbsd/master
 ```
 
-Resolve conflicts by deciding whether portable or OpenBSD owns the file.
+If merging a local cutover branch instead, use the local-clone preparation
+and fetch commands above in place of this fetch block.
+
+When the merge reports conflicts, it leaves the merge in progress. List the
+unresolved files, edit the conflict markers to combine the required portable
+and OpenBSD changes, then stage each resolved file:
+
+```sh
+git diff --name-only --diff-filter=U
+git diff -- path/to/file
+git add path/to/file
+```
+
+For files that should come entirely from one side, decide whether portable or
+OpenBSD owns the file before using the commands below. They replace the whole
+file, including changes outside the conflicting hunks.
 
 Useful commands:
 
@@ -140,11 +189,25 @@ git add path/to/file
 
 This takes the OpenBSD/cutover version of a conflicted file.
 
+For a modify/delete conflict, the side that deleted the file has no version
+to check out. For example, portable generates `Makefile` using autotools and
+does not track OpenBSD's `Makefile`. If Git reports that `Makefile` was deleted
+in HEAD and modified in cutover, keep the portable deletion with:
+
+```sh
+git rm -- Makefile
+```
+
+This removes the OpenBSD file left by the merge; regenerate the portable
+`Makefile` with your usual configure command before building. Use this only
+for the unmerged OpenBSD file, not an existing generated build file.
+
 Before committing, inspect the result:
 
 ```sh
 git status
 git diff --check
+git diff --cached --check
 git diff --cached --stat
 ```
 

cmd-attach-session.c

@@ -91,8 +91,10 @@ cmd_attach_session(struct cmdq_item *item, const char *tflag, int dflag,
 	wp = target.wp;
 
 	if (wl != NULL) {
-		if (wp != NULL)
+		if (wp != NULL) {
+			window_redraw_active_switch(wp->window, wp);
 			window_set_active_pane(wp->window, wp, 1);
+		}
 		session_set_current(s, wl);
 		if (wp != NULL)
 			cmd_find_from_winlink_pane(current, wl, wp, 0);

cmd-display-menu.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-display-menu.c,v 1.53 2026/08/31 07:46:55 nicm Exp $ */
+/* $OpenBSD: cmd-display-menu.c,v 1.55 2026/09/21 12:14:32 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -54,8 +54,8 @@ const struct cmd_entry cmd_display_popup_entry = {
 	.name = "display-popup",
 	.alias = "popup",
 
-	.args = { "Bb:Cc:d:e:Eh:kNs:S:t:T:w:x:y:", 0, -1, NULL },
-	.usage = "[-BCEkN] [-b border-lines] [-c target-client] "
+	.args = { "Bb:Cc:d:e:Eh:ks:S:t:T:w:x:y:", 0, -1, NULL },
+	.usage = "[-BCEk] [-b border-lines] [-c target-client] "
 		 "[-d start-directory] [-e environment] [-h height] "
 		 "[-s style] [-S border-style] " CMD_TARGET_PANE_USAGE
 		 " [-T title] [-w width] [-x position] [-y position] "
@@ -91,203 +91,6 @@ cmd_display_menu_args_parse(struct args *args, u_int idx, __unused char **cause)
 	return (type);
 }
 
-static int
-cmd_display_menu_get_popup_pos(struct client *tc, struct cmdq_item *item,
-    struct args *args, u_int *px, u_int *py, u_int w, u_int h)
-{
-	struct tty		*tty = &tc->tty;
-	struct cmd_find_state	*target = cmdq_get_target(item);
-	struct key_event	*event = cmdq_get_event(item);
-	struct session		*s = tc->session;
-	struct winlink		*wl = target->wl;
-	struct window_pane	*wp = target->wp;
-	struct style_ranges	*ranges = NULL;
-	struct style_range	*sr = NULL;
-	const char		*xp, *yp;
-	char			*p;
-	int			 top;
-	u_int			 line, ox, oy, sx, sy, lines, position;
-	long			 n;
-	struct format_tree	*ft;
-
-	/*
-	 * Work out the position from the -x and -y arguments. This is the
-	 * bottom-left position.
-	 */
-
-	/* If the popup is too big, stop now. */
-	if (w > tty->sx || h > tty->sy)
-		return (0);
-
-	/* Create format with mouse position if any. */
-	ft = format_create_from_target(item);
-	if (event->m.valid) {
-		format_add(ft, "popup_mouse_x", "%u", event->m.x);
-		format_add(ft, "popup_mouse_y", "%u", event->m.y);
-	}
-
-	/* Position of the previous menu, for -x/-y L. */
-	format_add(ft, "popup_last_x", "%u", target->w->menu_last_px);
-	format_add(ft, "popup_last_y", "%u", target->w->menu_last_py + h);
-
-	/*
-	 * If there are any status lines, add this window position and the
-	 * status line position.
-	 */
-	top = status_at_line(tc);
-	if (top != -1) {
-		lines = status_line_size(tc);
-		if (top == 0)
-			top = lines;
-		else
-			top = 0;
-		position = options_get_number(s->options, "status-position");
-
-		for (line = 0; line < lines; line++) {
-			ranges = &tc->status.entries[line].ranges;
-			TAILQ_FOREACH(sr, ranges, entry) {
-				if (sr->type != STYLE_RANGE_WINDOW)
-					continue;
-				if (sr->argument == (u_int)wl->idx)
-					break;
-			}
-			if (sr != NULL)
-				break;
-		}
-
-		if (sr != NULL) {
-			format_add(ft, "popup_window_status_line_x", "%u",
-			    sr->start);
-			if (position == 0) {
-				format_add(ft, "popup_window_status_line_y",
-				    "%u", line + 1 + h);
-			} else {
-				format_add(ft, "popup_window_status_line_y",
-				    "%u", tty->sy - lines + line);
-			}
-		}
-
-		if (position == 0)
-			format_add(ft, "popup_status_line_y", "%u", lines + h);
-		else {
-			format_add(ft, "popup_status_line_y", "%u",
-			    tty->sy - lines);
-		}
-	} else
-		top = 0;
-
-	/* Popup width and height. */
-	format_add(ft, "popup_width", "%u", w);
-	format_add(ft, "popup_height", "%u", h);
-
-	/* Position so popup is in the centre. */
-	n = (long)(tty->sx - 1) / 2 - w / 2;
-	if (n < 0)
-		format_add(ft, "popup_centre_x", "%u", 0);
-	else
-		format_add(ft, "popup_centre_x", "%ld", n);
-	n = (tty->sy - 1) / 2 + h / 2;
-	if (n >= tty->sy)
-		format_add(ft, "popup_centre_y", "%u", tty->sy - h);
-	else
-		format_add(ft, "popup_centre_y", "%ld", n);
-
-	/* Position of popup relative to mouse. */
-	if (event->m.valid) {
-		n = (long)event->m.x - w / 2;
-		if (n < 0)
-			format_add(ft, "popup_mouse_centre_x", "%u", 0);
-		else
-			format_add(ft, "popup_mouse_centre_x", "%ld", n);
-		n = event->m.y - h / 2;
-		if (n + h >= tty->sy) {
-			format_add(ft, "popup_mouse_centre_y", "%u",
-			    tty->sy - h);
-		} else
-			format_add(ft, "popup_mouse_centre_y", "%ld", n);
-		n = (long)event->m.y + h;
-		if (n >= tty->sy)
-			format_add(ft, "popup_mouse_top", "%u", tty->sy - 1);
-		else
-			format_add(ft, "popup_mouse_top", "%ld", n);
-		n = event->m.y - h;
-		if (n < 0)
-			format_add(ft, "popup_mouse_bottom", "%u", 0);
-		else
-			format_add(ft, "popup_mouse_bottom", "%ld", n);
-	}
-
-	/* Position in pane. */
-	tty_window_offset(&tc->tty, &ox, &oy, &sx, &sy);
-	n = top + wp->yoff - oy + h;
-	if (n >= tty->sy)
-		format_add(ft, "popup_pane_top", "%u", tty->sy - h);
-	else
-		format_add(ft, "popup_pane_top", "%ld", n);
-	format_add(ft, "popup_pane_bottom", "%u", top + wp->yoff + wp->sy - oy);
-	format_add(ft, "popup_pane_left", "%u", wp->xoff - ox);
-	n = (long)wp->xoff + wp->sx - ox - w;
-	if (n < 0)
-		format_add(ft, "popup_pane_right", "%u", 0);
-	else
-		format_add(ft, "popup_pane_right", "%ld", n);
-
-	/* Expand horizontal position. */
-	xp = args_get(args, 'x');
-	if (xp == NULL || strcmp(xp, "C") == 0)
-		xp = "#{popup_centre_x}";
-	else if (strcmp(xp, "R") == 0)
-		xp = "#{popup_pane_right}";
-	else if (strcmp(xp, "P") == 0)
-		xp = "#{popup_pane_left}";
-	else if (strcmp(xp, "M") == 0)
-		xp = "#{popup_mouse_centre_x}";
-	else if (strcmp(xp, "L") == 0)
-		xp = "#{popup_last_x}";
-	else if (strcmp(xp, "W") == 0)
-		xp = "#{popup_window_status_line_x}";
-	p = format_expand(ft, xp);
-	n = strtol(p, NULL, 10);
-	if (n + w >= tty->sx)
-		n = tty->sx - w;
-	else if (n < 0)
-		n = 0;
-	*px = n;
-	log_debug("%s: -x: %s = %s = %u (-w %u)", __func__, xp, p, *px, w);
-	free(p);
-
-	/* Expand vertical position  */
-	yp = args_get(args, 'y');
-	if (yp == NULL || strcmp(yp, "C") == 0)
-		yp = "#{popup_centre_y}";
-	else if (strcmp(yp, "P") == 0)
-		yp = "#{popup_pane_bottom}";
-	else if (strcmp(yp, "M") == 0)
-		yp = "#{popup_mouse_top}";
-	else if (strcmp(yp, "L") == 0)
-		yp = "#{popup_last_y}";
-	else if (strcmp(yp, "S") == 0)
-		yp = "#{popup_status_line_y}";
-	else if (strcmp(yp, "W") == 0)
-		yp = "#{popup_window_status_line_y}";
-	p = format_expand(ft, yp);
-	n = strtol(p, NULL, 10);
-	if (n < h)
-		n = 0;
-	else
-		n -= h;
-	if (n + h >= tty->sy)
-		n = tty->sy - h;
-	else if (n < 0)
-		n = 0;
-	*py = n;
-	log_debug("%s: -y: %s = %s = %u (-h %u)", __func__, yp, p, *py, h);
-	free(p);
-
-	format_free(ft);
-	return (1);
-}
-
 static int
 cmd_display_menu_get_menu_pos(struct client *tc, struct cmdq_item *item,
     struct args *args, u_int *px, u_int *py, u_int w, u_int h)
@@ -482,8 +285,8 @@ cmd_display_menu_exec(struct cmd *self, struct cmdq_item *item)
 	enum box_lines		 lines = BOX_LINES_DEFAULT;
 	char			*title, *cause = NULL;
 	int			 flags = 0, starting_choice = 0;
-	u_int			 px, py, i, count = args_count(args);
-	struct options		*o = target->s->curw->window->options;
+	u_int			 px, py, sx, sy, i, count = args_count(args);
+	struct options		*o = target->w->options;
 	struct options_entry	*oe;
 
 	if (args_has(args, 'C')) {
@@ -531,9 +334,6 @@ cmd_display_menu_exec(struct cmd *self, struct cmdq_item *item)
 	}
 	if (menu->count == 0)
 		goto out;
-	if (!cmd_display_menu_get_menu_pos(tc, item, args, &px, &py,
-	    menu->width + 4, menu->count + 2))
-		goto out;
 
 	value = args_get(args, 'b');
 	if (value != NULL) {
@@ -544,7 +344,11 @@ cmd_display_menu_exec(struct cmd *self, struct cmdq_item *item)
 			cmdq_error(item, "menu-border-lines %s", cause);
 			goto fail;
 		}
-	}
+	} else
+		lines = options_get_number(o, "menu-border-lines");
+	menu_get_size(menu, lines, &sx, &sy);
+	if (!cmd_display_menu_get_menu_pos(tc, item, args, &px, &py, sx, sy))
+		goto out;
 
 	if (args_has(args, 'O'))
 		flags |= MENU_STAYOPEN;
@@ -565,6 +369,22 @@ fail:
 	return (CMD_RETURN_ERROR);
 }
 
+static enum pane_lines
+cmd_display_popup_get_lines(const char *value, char **cause)
+{
+	const struct options_table_entry	*oe;
+
+	if (value == NULL)
+		value = "single";
+	else if (strcmp(value, "rounded") == 0)
+		value = "single";
+	else if (strcmp(value, "padded") == 0)
+		value = "spaces";
+
+	oe = options_search("pane-border-lines");
+	return (options_find_choice(oe, value, cause));
+}
+
 static enum cmd_retval
 cmd_display_popup_exec(struct cmd *self, struct cmdq_item *item)
 {
@@ -572,148 +392,199 @@ cmd_display_popup_exec(struct cmd *self, struct cmdq_item *item)
 	struct cmd_find_state	*target = cmdq_get_target(item);
 	struct session		*s = target->s;
 	struct client		*tc = cmdq_get_target_client(item);
-	struct tty		*tty = &tc->tty;
-	const char		*value, *shell, *shellcmd = NULL;
-	const char		*style = args_get(args, 's');
+	struct winlink		*wl = target->wl;
+	struct window		*w = wl->window;
+	struct window_pane	*wp = target->wp, *new_wp = NULL;
+	struct spawn_context	 sc = { 0 };
+	struct layout_cell	*lc = NULL;
+	struct layout_geometry	 lg;
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+	const char		*value, *style = args_get(args, 's');
 	const char		*border_style = args_get(args, 'S');
-	char			*cwd = NULL, *cause = NULL, **argv = NULL;
-	char			*title = NULL;
-	int			 modify = popup_present(tc);
-	int			 flags = -1, argc = 0;
-	enum box_lines		 lines = BOX_LINES_DEFAULT;
-	u_int			 px, py, w, h, count = args_count(args);
+	char			*cause = NULL, *title = NULL;
+	enum pane_lines		 lines = PANE_LINES_SINGLE;
+	u_int			 px, py, sx, sy, count = args_count(args);
 	struct args_value	*av;
-	struct environ		*env = NULL;
-	struct options		*o = s->curw->window->options;
-	struct options_entry	*oe;
+	long long		 ll;
 
 	if (args_has(args, 'C')) {
-		server_client_clear_overlay(tc);
+		if (w->modal != NULL)
+			server_kill_pane(w->modal);
 		return (CMD_RETURN_NORMAL);
 	}
 	if (tc->flags & CLIENT_CONTROL)
 		return (CMD_RETURN_NORMAL);
-	if (!modify && tc->overlay_draw != NULL)
+	if (w->modal != NULL)
 		return (CMD_RETURN_NORMAL);
 
-	if (!modify) {
-		h = tty->sy / 2;
-		if (args_has(args, 'h')) {
-			h = args_percentage(args, 'h', 1, tty->sy, tty->sy,
-			    &cause);
-			if (cause != NULL) {
-				cmdq_error(item, "height %s", cause);
-				goto fail;
-			}
-		}
-
-		w = tty->sx / 2;
-		if (args_has(args, 'w')) {
-			w = args_percentage(args, 'w', 1, tty->sx, tty->sx,
-			    &cause);
-			if (cause != NULL) {
-				cmdq_error(item, "width %s", cause);
-				goto fail;
-			}
-		}
-
-		if (w > tty->sx)
-			w = tty->sx;
-		if (h > tty->sy)
-			h = tty->sy;
-		if (!cmd_display_menu_get_popup_pos(tc, item, args, &px, &py,
-		    w, h))
-			goto out;
-
-		value = args_get(args, 'd');
-		if (value != NULL)
-			cwd = format_single_from_target(item, value);
-		else
-			cwd = xstrdup(server_client_get_cwd(tc, s));
-		if (count == 0) {
-			shellcmd = options_get_string(s->options,
-			    "default-command");
-		} else if (count == 1)
-			shellcmd = args_string(args, 0);
-		if (count <= 1 && (shellcmd == NULL || *shellcmd == '\0')) {
-			shellcmd = NULL;
-			shell = options_get_string(s->options, "default-shell");
-			if (!checkshell(shell))
-				shell = _PATH_BSHELL;
-			cmd_append_argv(&argc, &argv, shell);
-		} else
-			args_to_vector(args, &argc, &argv);
-
-		if (args_has(args, 'e') >= 1) {
-			env = environ_create();
-			av = args_first_value(args, 'e');
-			while (av != NULL) {
-				environ_put(env, av->string, 0);
-				av = args_next_value(av);
-			}
-		}
-	}
-
 	value = args_get(args, 'b');
 	if (args_has(args, 'B'))
-		lines = BOX_LINES_NONE;
+		lines = PANE_LINES_NONE;
 	else if (value != NULL) {
-		oe = options_get(o, "popup-border-lines");
-		lines = options_find_choice(options_table_entry(oe), value,
-		    &cause);
+		lines = cmd_display_popup_get_lines(value, &cause);
 		if (cause != NULL) {
-			cmdq_error(item, "popup-border-lines %s", cause);
+			cmdq_error(item, "pane-border-lines %s", cause);
 			goto fail;
 		}
 	}
 
+	sy = w->sy / 2;
+	if (args_has(args, 'h')) {
+		ll = args_percentage(args, 'h', 1, w->sy, w->sy, &cause);
+		if (cause != NULL) {
+			cmdq_error(item, "height %s", cause);
+			goto fail;
+		}
+		sy = ll;
+	}
+
+	sx = w->sx / 2;
+	if (args_has(args, 'w')) {
+		ll = args_percentage(args, 'w', 1, w->sx, w->sx, &cause);
+		if (cause != NULL) {
+			cmdq_error(item, "width %s", cause);
+			goto fail;
+		}
+		sx = ll;
+	}
+
+	if (sx > w->sx)
+		sx = w->sx;
+	if (sy > w->sy)
+		sy = w->sy;
+	if ((lines == PANE_LINES_NONE && (sx < 1 || sy < 1)) ||
+	    (lines != PANE_LINES_NONE && (sx < 3 || sy < 3)))
+		goto out;
+	if (!cmd_display_menu_get_menu_pos(tc, item, args, &px, &py, sx, sy))
+		goto out;
+
+	lg.sx = sx;
+	lg.sy = sy;
+	lg.xoff = px;
+	lg.yoff = py;
+	if (lines != PANE_LINES_NONE) {
+		lg.sx -= 2;
+		lg.sy -= 2;
+		lg.xoff++;
+		lg.yoff++;
+	}
+
+	window_push_zoom(w, 0, 1);
+	lc = layout_floating_pane(w, wp, &lg);
+	if (lc == NULL) {
+		window_pop_zoom(w);
+		goto out;
+	}
+
+	sc.item = item;
+	sc.s = s;
+	sc.wl = wl;
+	sc.tc = tc;
+	sc.wp0 = wp;
+	sc.lc = lc;
+	sc.idx = -1;
+	sc.cwd = args_get(args, 'd');
+	sc.flags = (SPAWN_FLOATING|SPAWN_MODAL|SPAWN_FLOATOVERZOOM);
+
+	if (count != 1 || *args_string(args, 0) != '\0')
+		args_to_vector(args, &sc.argc, &sc.argv);
+	sc.environ = environ_create();
+	av = args_first_value(args, 'e');
+	while (av != NULL) {
+		environ_put(sc.environ, av->string, 0);
+		av = args_next_value(av);
+	}
+
+	new_wp = spawn_pane(&sc, &cause);
+	if (new_wp == NULL) {
+		cmdq_error(item, "create pane failed: %s", cause);
+		free(cause);
+		cause = NULL;
+		window_pop_zoom(w);
+		goto fail;
+	}
+	window_pop_zoom(w);
+	new_wp->flags |= PANE_CAPTUREALLKEYS;
+	if (!args_has(args, 'E'))
+		new_wp->flags |= PANE_CLOSEONCANCEL;
+
+	options_set_number(new_wp->options, "pane-border-lines", lines);
+	if (args_has(args, 'E') > 1) {
+		if (args_has(args, 'k'))
+			options_set_number(new_wp->options, "remain-on-exit", 4);
+		else
+			options_set_number(new_wp->options, "remain-on-exit", 2);
+	} else if (args_has(args, 'E'))
+		options_set_number(new_wp->options, "remain-on-exit", 0);
+	else if (args_has(args, 'k'))
+		options_set_number(new_wp->options, "remain-on-exit", 3);
+	else
+		options_set_number(new_wp->options, "remain-on-exit", 1);
+	options_set_string(new_wp->options, "remain-on-exit-format", 0, "%s", "");
+
+	if (style != NULL) {
+		if (options_set_string(new_wp->options, "window-style", 0,
+		    "%s", style) == NULL) {
+			cmdq_error(item, "bad style: %s", style);
+			goto fail;
+		}
+		options_set_string(new_wp->options, "window-active-style", 0,
+		    "%s", style);
+		new_wp->flags |= (PANE_REDRAW|PANE_STYLECHANGED|
+		    PANE_THEMECHANGED);
+	}
+	if (border_style != NULL) {
+		if (options_set_string(new_wp->options, "pane-border-style", 0,
+		    "%s", border_style) == NULL) {
+			cmdq_error(item, "bad border style: %s", border_style);
+			goto fail;
+		}
+		options_set_string(new_wp->options, "pane-active-border-style",
+		    0, "%s", border_style);
+	}
 	if (args_has(args, 'T'))
 		title = format_single_from_target(item, args_get(args, 'T'));
-	else
-		title = xstrdup("");
-
-	if (args_has(args, 'N') || !modify)
-		flags = 0;
-	if (args_has(args, 'E') > 1) {
-		if (flags == -1)
-			flags = 0;
-		flags |= POPUP_CLOSEEXITZERO;
-	} else if (args_has(args, 'E')) {
-		if (flags == -1)
-			flags = 0;
-		flags |= POPUP_CLOSEEXIT;
-	}
-	if (args_has(args, 'k')) {
-		if (flags == -1)
-			flags = 0;
-		flags |= POPUP_CLOSEANYKEY;
+	if (title != NULL) {
+		options_set_number(new_wp->options, "pane-border-status",
+		    PANE_STATUS_TOP);
+		options_set_string(new_wp->options, "pane-border-format", 0,
+		    "%s", "#{pane_title}");
+		screen_set_title(&new_wp->base, title, 0);
+		ep = event_payload_create();
+		cmd_find_from_pane(&fs, new_wp, 0);
+		event_payload_set_target(ep, &fs);
+		event_payload_set_pane(ep, "pane", new_wp);
+		event_payload_set_window(ep, "window", new_wp->window);
+		event_payload_set_string(ep, "new_title", "%s", title);
+		events_fire("pane-title-changed", ep);
 	}
 
-	if (modify) {
-		popup_modify(tc, title, style, border_style, lines, flags);
-		goto out;
-	}
-	if (popup_display(flags, lines, item, px, py, w, h, env, shellcmd, argc,
-	    argv, cwd, title, tc, s, style, border_style, NULL, NULL) != 0)
-		goto out;
-	environ_free(env);
-	free(cwd);
+	new_wp->wait_item = item;
+	server_redraw_session(s);
+	if (sc.argv != NULL)
+		cmd_free_argv(sc.argc, sc.argv);
+	environ_free(sc.environ);
 	free(title);
-	cmd_free_argv(argc, argv);
 	return (CMD_RETURN_WAIT);
 
 out:
-	cmd_free_argv(argc, argv);
-	environ_free(env);
-	free(cwd);
+	if (sc.argv != NULL)
+		cmd_free_argv(sc.argc, sc.argv);
+	environ_free(sc.environ);
 	free(title);
 	return (CMD_RETURN_NORMAL);
 
 fail:
 	free(cause);
-	cmd_free_argv(argc, argv);
-	environ_free(env);
-	free(cwd);
+	if (new_wp != NULL) {
+		server_client_remove_pane(new_wp);
+		layout_close_pane(new_wp);
+		window_remove_pane(new_wp->window, new_wp);
+	}
+	if (sc.argv != NULL)
+		cmd_free_argv(sc.argc, sc.argv);
+	environ_free(sc.environ);
 	free(title);
 	return (CMD_RETURN_ERROR);
 }

cmd-join-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-join-pane.c,v 1.74 2026/08/03 20:29:52 nicm Exp $ */
+/* $OpenBSD: cmd-join-pane.c,v 1.75 2026/09/21 10:33:16 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 George Nachman <tmux@georgester.com>
@@ -133,7 +133,7 @@ cmd_join_pane_place(struct cmdq_item *item, struct winlink *wl,
 	} else if (strcmp(position, "back") == 0) {
 		TAILQ_REMOVE(&w->z_index, wp, zentry);
 		TAILQ_FOREACH(owp, &w->z_index, zentry) {
-			if (!window_pane_is_floating(owp))
+			if (!window_pane_is_floating_with_hidden(owp))
 				break;
 		}
 		if (owp != NULL)
@@ -142,24 +142,30 @@ cmd_join_pane_place(struct cmdq_item *item, struct winlink *wl,
 			TAILQ_INSERT_TAIL(&w->z_index, wp, zentry);
 	} else if (strcmp(position, "forward") == 0) {
 		owp = TAILQ_PREV(wp, window_panes_zindex, zentry);
+		while (owp != NULL && owp->layout_cell == NULL)
+			owp = TAILQ_PREV(owp, window_panes_zindex, zentry);
 		if (owp != NULL) {
 			TAILQ_REMOVE(&w->z_index, wp, zentry);
 			TAILQ_INSERT_BEFORE(owp, wp, zentry);
 		}
 	} else if (strcmp(position, "backward") == 0) {
 		owp = TAILQ_NEXT(wp, zentry);
+		while (owp != NULL && owp->layout_cell == NULL)
+			owp = TAILQ_NEXT(owp, zentry);
 		if (owp != NULL && window_pane_is_floating(owp)) {
 			TAILQ_REMOVE(&w->z_index, wp, zentry);
 			TAILQ_INSERT_AFTER(&w->z_index, owp, wp, zentry);
 		}
 	} else if (strcmp(position, "forward-loop") == 0) {
 		owp = TAILQ_PREV(wp, window_panes_zindex, zentry);
+		while (owp != NULL && owp->layout_cell == NULL)
+			owp = TAILQ_PREV(owp, window_panes_zindex, zentry);
 		TAILQ_REMOVE(&w->z_index, wp, zentry);
 		if (owp != NULL)
 			TAILQ_INSERT_BEFORE(owp, wp, zentry);
 		else {
 			TAILQ_FOREACH(owp, &w->z_index, zentry) {
-				if (!window_pane_is_floating(owp))
+				if (!window_pane_is_floating_with_hidden(owp))
 					break;
 			}
 			if (owp != NULL)
@@ -169,6 +175,8 @@ cmd_join_pane_place(struct cmdq_item *item, struct winlink *wl,
 		}
 	} else if (strcmp(position, "backward-loop") == 0) {
 		owp = TAILQ_NEXT(wp, zentry);
+		while (owp != NULL && owp->layout_cell == NULL)
+			owp = TAILQ_NEXT(owp, zentry);
 		if (owp != NULL && window_pane_is_floating(owp)) {
 			TAILQ_REMOVE(&w->z_index, wp, zentry);
 			TAILQ_INSERT_AFTER(&w->z_index, owp, wp, zentry);
@@ -299,7 +307,7 @@ cmd_join_pane_mouse_move(struct client *c, struct mouse_event *m)
 	struct window		*w;
 	struct window_pane	*wp;
 	struct layout_cell	*lc;
-	int			 y, ly, x, lx;
+	int			 y, ly, x, lx, oxoff, oyoff, osx, osy;
 
 	wp = cmd_mouse_pane(m, NULL, &wl);
 	if (wp == NULL) {
@@ -321,10 +329,16 @@ cmd_join_pane_mouse_move(struct client *c, struct mouse_event *m)
 		ly = m->statusat - 1;
 
 	if (x != lx || y != ly) {
+		oxoff = wp->xoff;
+		oyoff = wp->yoff;
+		osx = wp->sx;
+		osy = wp->sy;
+
 		lc->g.xoff += x - lx;
 		lc->g.yoff += y - ly;
 		layout_fix_panes(w, NULL);
-		server_redraw_window(w);
+
+		window_redraw_floating_pane(wp, oxoff, oyoff, osx, osy);
 		server_redraw_window_borders(w);
 	}
 }
@@ -347,8 +361,10 @@ cmd_join_pane_zindex(struct cmdq_item *item, struct winlink *wl,
 
 	n = 0;
 	TAILQ_FOREACH(owp, &w->z_index, zentry) {
-		if (!window_pane_is_floating(owp))
+		if (!window_pane_is_floating_with_hidden(owp))
 			break;
+		if (owp->layout_cell == NULL)
+			continue;
 		if (n >= z)
 			break;
 		n++;
@@ -443,7 +459,6 @@ cmd_join_pane_exec(struct cmd *self, struct cmdq_item *item)
 				cmdq_error(item, "pane is not floating");
 				return (CMD_RETURN_ERROR);
 			}
-			server_unzoom_window(dst_w);
 			if ((s = args_get(args, 'P')) != NULL)
 				return (cmd_join_pane_place(item, dst_wl, dst_wp, s));
 			if ((s = args_get(args, 'z')) != NULL)

cmd-queue.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-queue.c,v 1.123 2026/08/24 20:34:26 nicm Exp $ */
+/* $OpenBSD: cmd-queue.c,v 1.124 2026/09/22 06:46:50 nicm Exp $ */
 
 /*
  * Copyright (c) 2013 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -580,6 +580,9 @@ cmdq_fire_command(struct cmdq_item *item)
 	int			 flags, quiet = 0;
 	char			*tmp;
 
+	if (item->client != NULL && (item->client->flags & CLIENT_DEAD))
+		return (CMD_RETURN_ERROR);
+
 	if (cfg_finished)
 		cmdq_add_message(item);
 	if (log_get_level() > 1) {

cmd-resize-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-resize-pane.c,v 1.68 2026/08/31 07:44:39 nicm Exp $ */
+/* $OpenBSD: cmd-resize-pane.c,v 1.69 2026/09/21 10:33:16 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -91,7 +91,8 @@ cmd_resize_pane_exec(struct cmd *self, struct cmdq_item *item)
 		server_redraw_window(w);
 		return (CMD_RETURN_NORMAL);
 	}
-	server_unzoom_window(w);
+	if (!window_pane_is_floating(wp))
+		server_unzoom_window(w);
 	lc = wp->layout_cell; /* may have been replaced by unzoom */
 
 	if (args_has(args, 'x')) {
@@ -236,8 +237,8 @@ cmd_resize_pane_mouse_resize_move_floating(struct client *c,
 	struct window_pane	*wp;
 	struct layout_cell	*lc;
 	int			 y, ly, x, lx, sx, sy, new_sx, new_sy;
-	int			 left, right;
-	int			 new_xoff, new_yoff, resizes = 0;
+	int			 left, right, resizes = 0;
+	int			 new_xoff, new_yoff, old_xoff, old_yoff;
 
 	wp = cmd_mouse_pane(m, NULL, &wl);
 	if (wp == NULL) {
@@ -248,6 +249,8 @@ cmd_resize_pane_mouse_resize_move_floating(struct client *c,
 	lc = wp->layout_cell;
 	sx = wp->sx;
 	sy = wp->sy;
+	old_xoff = wp->xoff;
+	old_yoff = wp->yoff;
 	left = wp->xoff - 1;
 	right = wp->xoff + sx;
 	if (window_pane_scrollbar_reserve(wp) &&
@@ -347,7 +350,7 @@ cmd_resize_pane_mouse_resize_move_floating(struct client *c,
 	}
 	if (resizes != 0) {
 		layout_fix_panes(w, NULL);
-		server_redraw_window(w);
+		window_redraw_floating_pane(wp, old_xoff, old_yoff, sx, sy);
 		server_redraw_window_borders(w);
 	}
 }

cmd-run-shell.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-run-shell.c,v 1.94 2026/08/25 06:04:33 nicm Exp $ */
+/* $OpenBSD: cmd-run-shell.c,v 1.95 2026/09/20 07:59:55 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Tiago Cunha <me@tiagocunha.org>
@@ -164,7 +164,7 @@ cmd_run_shell_exec(struct cmd *self, struct cmdq_item *item)
 	if (cdata->client != NULL)
 		cdata->client->references++;
 	if (args_has(args, 'c'))
-		cdata->cwd = xstrdup(args_get(args, 'c'));
+		cdata->cwd = format_single_from_target(item, args_get(args, 'c'));
 	else
 		cdata->cwd = xstrdup(server_client_get_cwd(c, s));
 

cmd-split-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-split-window.c,v 1.150 2026/08/20 09:19:24 nicm Exp $ */
+/* $OpenBSD: cmd-split-window.c,v 1.151 2026/09/10 11:02:18 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -40,8 +40,8 @@ const struct cmd_entry cmd_new_pane_entry = {
 	.name = "new-pane",
 	.alias = "newp",
 
-	.args = { "AbB:Cc:de:EfF:hIkl:KLMm:Op:PR:s:S:t:T:vWx:X:y:Y:Z", 0, -1, NULL },
-	.usage = "[-AbCdefhIkKLMOPvWZ] [-B border-lines] "
+	.args = { "AbB:Cc:Dde:EfF:hIkl:KLMm:Op:PR:s:S:t:T:vWx:X:y:Y:Z", 0, -1, NULL },
+	.usage = "[-AbCDefhIkKLMOPvWZ] [-B border-lines] "
 		 "[-c start-directory] [-e environment] "
 		 "[-F format] [-l size] [-m message] [-p percentage] "
 		 "[-s style] [-S active-border-style] "
@@ -219,6 +219,8 @@ cmd_split_window_exec(struct cmd *self, struct cmdq_item *item)
 		new_wp->flags |= PANE_CAPTUREALLKEYS;
 	if (args_has(args, 'C') && args_has(args, 'O'))
 		new_wp->flags |= PANE_CLOSEONCLICK;
+	if (args_has(args, 'D') && args_has(args, 'O'))
+		new_wp->flags |= PANE_CLOSEONCANCEL;
 
 	style = args_get(args, 's');
 	if (style != NULL) {
@@ -360,6 +362,7 @@ cmd_split_window_mouse_resize(struct client *c, struct mouse_event *m)
 	enum pane_lines		 lines;
 	u_int			 sx, sy;
 	int			 x, y, xoff, yoff, border;
+	int			 oxoff, oyoff, osx, osy;
 
 	if (c->tty.mouse_last_pane == -1)
 		return;
@@ -415,8 +418,14 @@ cmd_split_window_mouse_resize(struct client *c, struct mouse_event *m)
 	if (sy < PANE_MINIMUM)
 		sy = PANE_MINIMUM;
 
+	oxoff = wp->xoff;
+	oyoff = wp->yoff;
+	osx = wp->sx;
+	osy = wp->sy;
+
 	layout_set_size(lc, sx, sy, xoff, yoff);
 	layout_fix_panes(w, NULL);
-	server_redraw_window(w);
+
+	window_redraw_floating_pane(wp, oxoff, oyoff, osx, osy);
 	server_redraw_window_borders(w);
 }

cmd-wait-for.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-wait-for.c,v 1.23 2026/07/10 13:38:45 nicm Exp $ */
+/* $OpenBSD: cmd-wait-for.c,v 1.24 2026/09/22 06:46:50 nicm Exp $ */
 
 /*
  * Copyright (c) 2013 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -480,6 +480,40 @@ cmd_wait_for_unlock(struct cmdq_item *item, const char *name,
 	return (CMD_RETURN_NORMAL);
 }
 
+void
+cmd_wait_for_client_lost(struct client *c)
+{
+	struct wait_channel	*wc, *wc1;
+	struct wait_item	*wi, *wi1;
+	struct wait_event_item	*wei, *wei1;
+
+	TAILQ_FOREACH_SAFE(wei, &wait_event_items, entry, wei1) {
+		if (cmdq_get_client(wei->item) == c) {
+			TAILQ_REMOVE(&wait_event_items, wei, entry);
+			cmdq_continue(wei->item);
+			cmd_wait_for_event_free(wei);
+		}
+	}
+
+	RB_FOREACH_SAFE(wc, wait_channels, &wait_channels, wc1) {
+		TAILQ_FOREACH_SAFE(wi, &wc->waiters, entry, wi1) {
+			if (cmdq_get_client(wi->item) == c) {
+				cmdq_continue(wi->item);
+				TAILQ_REMOVE(&wc->waiters, wi, entry);
+				free(wi);
+			}
+		}
+		TAILQ_FOREACH_SAFE(wi, &wc->lockers, entry, wi1) {
+			if (cmdq_get_client(wi->item) == c) {
+				cmdq_continue(wi->item);
+				TAILQ_REMOVE(&wc->lockers, wi, entry);
+				free(wi);
+			}
+		}
+		cmd_wait_for_remove_empty(wc);
+	}
+}
+
 void
 cmd_wait_for_flush(void)
 {

configure.ac

@@ -1,6 +1,6 @@
 # configure.ac
 
-AC_INIT([tmux], next-3.8)
+AC_INIT([tmux], next-3.9)
 AC_PREREQ([2.60])
 
 AC_CONFIG_AUX_DIR(etc)

format.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: format.c,v 1.417 2026/09/08 15:42:26 nicm Exp $ */
+/* $OpenBSD: format.c,v 1.418 2026/09/20 08:19:31 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -2876,10 +2876,10 @@ format_cb_session_activity_flag(struct format_tree *ft)
 
 	if (ft->s != NULL) {
 		RB_FOREACH(wl, winlinks, &ft->s->windows) {
-			if (ft->wl->flags & WINLINK_ACTIVITY)
+			if (wl->flags & WINLINK_ACTIVITY)
 				return (xstrdup("1"));
-			return (xstrdup("0"));
 		}
+		return (xstrdup("0"));
 	}
 	return (NULL);
 }
@@ -2894,8 +2894,8 @@ format_cb_session_bell_flag(struct format_tree *ft)
 		RB_FOREACH(wl, winlinks, &ft->s->windows) {
 			if (wl->flags & WINLINK_BELL)
 				return (xstrdup("1"));
-			return (xstrdup("0"));
 		}
+		return (xstrdup("0"));
 	}
 	return (NULL);
 }
@@ -2908,10 +2908,10 @@ format_cb_session_silence_flag(struct format_tree *ft)
 
 	if (ft->s != NULL) {
 		RB_FOREACH(wl, winlinks, &ft->s->windows) {
-			if (ft->wl->flags & WINLINK_SILENCE)
+			if (wl->flags & WINLINK_SILENCE)
 				return (xstrdup("1"));
-			return (xstrdup("0"));
 		}
+		return (xstrdup("0"));
 	}
 	return (NULL);
 }

fuzz/input-fuzzer.c

@@ -44,7 +44,7 @@ LLVMFuzzerTestOneInput(const u_char *data, size_t size)
 	w = window_create(PANE_WIDTH, PANE_HEIGHT, 0, 0);
 	wp = window_add_pane(w, NULL, 0, 0);
 	bufferevent_pair_new(libevent, BEV_OPT_CLOSE_ON_FREE, vpty);
-	wp->ictx = input_init(wp, vpty[0], NULL, NULL);
+	wp->ictx = input_init(wp, vpty[0], NULL);
 	window_add_ref(w, __func__);
 
 	wp->fd = open("/dev/null", O_WRONLY);

fuzz/layout-fuzzer.c

@@ -0,0 +1,111 @@
+/*
+ * Copyright (c) 2026 Arthur Chan <arthur.chan@adalogics.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*
+ * Fuzz the custom layout parser.
+ *
+ * A layout string such as "bb62,80x24,0,0{40x24,0,0,1,39x24,41,0,2}" is
+ * accepted by select-layout and is what tmux stores and restores for a
+ * window, so it is parsed from configuration and from commands. It drives
+ * layout-custom.c (the string parser and the checksum), then layout.c, which
+ * resizes and assigns the cells.
+ *
+ * layout_parse() refuses a window with no panes, and refuses a layout whose
+ * cell count is smaller than the pane count, so the window is given a fixed
+ * number of panes. The count is fixed rather than derived from the input, so
+ * a mutation always means a different layout string.
+ */
+
+#include <sys/types.h>
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "tmux.h"
+
+#define FUZZER_MAXLEN 1024
+#define FUZZER_PANES 4
+
+struct event_base	*libevent;
+
+int
+LLVMFuzzerTestOneInput(const u_char *data, size_t size)
+{
+	struct window		*w;
+	struct window_pane	*wp;
+	char			*buf, *cause = NULL, *dump;
+	u_int			 i;
+
+	if (size == 0 || size > FUZZER_MAXLEN)
+		return 0;
+
+	/* layout_parse() takes a C string. */
+	buf = malloc(size + 1);
+	if (buf == NULL)
+		return 0;
+	memcpy(buf, data, size);
+	buf[size] = '\0';
+
+	w = window_create(80, 24, 0, 0);
+	if (w == NULL) {
+		free(buf);
+		return 0;
+	}
+	window_add_ref(w, __func__);
+
+	for (i = 0; i < FUZZER_PANES; i++) {
+		wp = window_add_pane(w, NULL, 0, 0);
+		if (w->active == NULL)
+			w->active = wp;
+	}
+
+	if (layout_parse(w, buf, &cause) == 0) {
+		dump = layout_dump(w, w->layout_root, 1);
+		free(dump);
+	}
+	free(cause);
+
+	window_remove_ref(w, __func__);
+
+	free(buf);
+	return 0;
+}
+
+int
+LLVMFuzzerInitialize(__unused int *argc, __unused char ***argv)
+{
+	const struct options_table_entry	*oe;
+
+	global_environ = environ_create();
+	global_options = options_create(NULL);
+	global_s_options = options_create(NULL);
+	global_w_options = options_create(NULL);
+	for (oe = options_table; oe->name != NULL; oe++) {
+		if (oe->scope & OPTIONS_TABLE_SERVER)
+			options_default(global_options, oe);
+		if (oe->scope & OPTIONS_TABLE_SESSION)
+			options_default(global_s_options, oe);
+		if (oe->scope & OPTIONS_TABLE_WINDOW)
+			options_default(global_w_options, oe);
+	}
+
+	libevent = osdep_event_init();
+
+	socket_path = xstrdup("dummy");
+
+	return 0;
+}

fuzz/layout-fuzzer.dict

@@ -0,0 +1,17 @@
+# tmux custom layout strings: "<checksum>,<sx>x<sy>,<x>,<y>{...}" / "[...]"
+","
+"x"
+"{"
+"}"
+"["
+"]"
+"0"
+"1"
+"80x24,0,0"
+"40x24,0,0"
+"bb62,"
+"cafe,"
+",0,0,0"
+",0,0{"
+",0,0["
+"@"

fuzz/layout-fuzzer.options

@@ -0,0 +1,2 @@
+[libfuzzer]
+max_len = 1024

input.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: input.c,v 1.271 2026/08/31 19:34:09 nicm Exp $ */
+/* $OpenBSD: input.c,v 1.272 2026/09/21 10:22:31 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -101,7 +101,6 @@ struct input_ctx {
 	struct bufferevent	       *event;
 	struct screen_write_ctx		ctx;
 	struct colour_palette	       *palette;
-	struct client		       *c;
 
 	struct input_cell		cell;
 	struct input_cell		old_cell;
@@ -874,7 +873,7 @@ input_restore_state(struct input_ctx *ictx)
 /* Initialise input parser. */
 struct input_ctx *
 input_init(struct window_pane *wp, struct bufferevent *bev,
-    struct colour_palette *palette, struct client *c)
+    struct colour_palette *palette)
 {
 	struct input_ctx	*ictx;
 
@@ -882,7 +881,6 @@ input_init(struct window_pane *wp, struct bufferevent *bev,
 	ictx->wp = wp;
 	ictx->event = bev;
 	ictx->palette = palette;
-	ictx->c = c;
 
 	ictx->input_space = INPUT_BUF_START;
 	ictx->input_buf = xmalloc(INPUT_BUF_START);
@@ -3425,15 +3423,9 @@ input_osc_52(struct input_ctx *ictx, const char *p)
 		return;
 
 	if (wp == NULL) {
-		/* Popup window. */
-		if (ictx->c == NULL) {
-			free(out);
-			return;
-		}
-		tty_set_selection(&ictx->c->tty, clip, out, outlen);
-		paste_add(NULL, out, outlen);
+		free(out);
+		return;
 	} else {
-		/* Normal window. */
 		screen_write_start_pane(&ctx, wp, NULL);
 		screen_write_setselection(&ctx, clip, out, outlen);
 		screen_write_stop(&ctx);

key-bindings.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: key-bindings.c,v 1.192 2026/08/06 09:05:04 nicm Exp $ */
+/* $OpenBSD: key-bindings.c,v 1.193 2026/09/21 20:45:48 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -523,7 +523,7 @@ key_bindings_init(void)
 		"bind -n TripleClick1Pane { select-pane -t=; if -F '#{||:#{pane_in_mode},#{mouse_any_flag}}' { send -M } { copy-mode -H; send -X select-line; run -d0.3; send -X copy-pipe-and-cancel } }",
 
 		/* Mouse button 1 on border. */
-		"bind -n MouseDown1Border { select-pane -M }",
+		"bind -n MouseDown1Border { select-pane -t= }",
 
 		/* Mouse button 1 drag on border. */
 		"bind -n MouseDrag1Border { resize-pane -M }",

layout-custom.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: layout-custom.c,v 1.40 2026/09/09 07:03:39 nicm Exp $ */
+/* $OpenBSD: layout-custom.c,v 1.43 2026/09/22 06:48:01 nicm Exp $ */
 
 /*
  * Copyright (c) 2010 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -28,8 +28,8 @@
 #include "tmux.h"
 
 /*
- * Layouts can be represented as strings in a JSON format (v2). The legacy
- * format (v1) will be removed in the future and should no longer be used.
+ * Layouts can be represented as strings in a JSON format (v2). The version 1
+ * format will be removed in the future and should no longer be used.
  *
  * The current (v2) format is JSON. The top level has two keys:
  *    "V": version number, currently 2
@@ -57,6 +57,9 @@
  *    "z": z-index, if a floating pane
  */
 
+/* Maximum nesting depth for version 1 layouts. */
+#define LAYOUT_V1_MAX_DEPTH 1000
+
 /* Layout string. */
 struct layout_string {
 	char	*dat;
@@ -280,26 +283,59 @@ layout_checksum(const char *layout)
 char *
 layout_dump(__unused struct window *w, struct layout_cell *lcroot, int flags)
 {
-	struct layout_string	 layout_string;
-	char			*out = NULL;
+	struct layout_string	 layout_string = { 0 };
+	char			*out;
 
 	if (lcroot == NULL)
-		return NULL;
-
+		goto bad;
 	layout_string_init(&layout_string);
-
-	if (layout_append(lcroot, &layout_string, flags) == 0) {
-		if (flags & LAYOUT_CUSTOM_OLD_FORMAT)
-			xasprintf(&out, "%04hx,%s",
-			    layout_checksum(layout_string.dat),
-			    layout_string.dat);
-		else
-			xasprintf(&out, "{\"V\":2,\"L\":%s}",
-			    layout_string.dat);
+	if (layout_append(lcroot, &layout_string, flags) != 0)
+		goto bad;
+	if (~flags & LAYOUT_CUSTOM_OLD_FORMAT)
+		xasprintf(&out, "{\"V\":2,\"L\":%s}", layout_string.dat);
+	else {
+		xasprintf(&out, "%04hx,%s", layout_checksum(layout_string.dat),
+		    layout_string.dat);
 	}
 	layout_string_free(&layout_string);
-
 	return (out);
+
+bad:
+	layout_string_free(&layout_string);
+	if (~flags & LAYOUT_CUSTOM_OLD_FORMAT)
+		return (NULL);
+	return (xstrdup("0000,"));
+}
+
+/* Get a floating pane cell's z-index in the layout being dumped. */
+static u_int
+layout_cell_zindex(struct layout_cell *lc)
+{
+	struct window_pane	*wp = lc->wp, *wq;
+	struct window		*w = wp->window;
+	struct layout_cell	*other;
+	int			 saved = (lc == wp->saved_layout_cell);
+	u_int			 i = 0;
+
+	if (saved &&
+	    w->active != NULL &&
+	    (w->active->flags & PANE_ZOOMED) &&
+	    (w->active->saved_layout_cell->flags & LAYOUT_CELL_FLOATING)) {
+		if (wp == w->active)
+			return (0);
+		i++;
+	}
+	TAILQ_FOREACH(wq, &w->z_index, zentry) {
+		if (wq == wp)
+			break;
+		if (saved)
+			other = wq->saved_layout_cell;
+		else
+			other = wq->layout_cell;
+		if (other != NULL && (other->flags & LAYOUT_CELL_FLOATING))
+			i++;
+	}
+	return (i);
 }
 
 /* Append information for a single cell in a JSON (v2) format. */
@@ -310,7 +346,7 @@ layout_append_v2(struct layout_cell *lc, struct layout_string *ls)
 	struct window_pane	*wp;
 	enum layout_type	 type;
 	char			 c;
-	u_int			 i, n;
+	u_int			 i, n, z;
 
 	if (lc == NULL)
 		return (-1);
@@ -351,9 +387,10 @@ layout_append_v2(struct layout_cell *lc, struct layout_string *ls)
 		if (window_pane_index(wp, &i) != 0)
 			return (-1);
 		layout_string_write(ls, ",\"i\":%u", i);
-		if ((lc->flags & LAYOUT_CELL_FLOATING) &&
-		    window_pane_zindex(wp, &i) == 0)
-			layout_string_write(ls, ",\"z\":%u", i);
+		if (lc->flags & LAYOUT_CELL_FLOATING) {
+			z = layout_cell_zindex(lc);
+			layout_string_write(ls, ",\"z\":%u", z);
+		}
 		layout_string_write(ls, ",\"I\":\"%%%u\"", wp->id);
 	}
 
@@ -362,7 +399,7 @@ layout_append_v2(struct layout_cell *lc, struct layout_string *ls)
 	return (0);
 }
 
-/* Append information for a single cell in the legacy (v1) format. */
+/* Append information for a single cell in the version 1 format. */
 static int
 layout_append_v1(struct layout_cell *lc, struct layout_string *ls)
 {
@@ -778,7 +815,7 @@ layout_assign(struct window *w, struct layout_parse_ctx *pctx)
 		layout_assign_fallback(w, w->layout_root);
 }
 
-/* Construct a cell from the legacy (v1) format. */
+/* Construct a cell from the version 1 format. */
 static struct layout_cell *
 layout_construct_cell(struct layout_cell *lcparent, const char **layout)
 {
@@ -827,12 +864,15 @@ layout_construct_cell(struct layout_cell *lcparent, const char **layout)
 	return (lc);
 }
 
-/* Construct a layout from the legacy (v1) format. */
+/* Construct a layout from the version 1 format. */
 static struct layout_cell *
-layout_construct_v1(struct layout_cell *lcparent, const char **layout)
+layout_construct_v1(struct layout_cell *lcparent, const char **layout, u_int depth)
 {
 	struct layout_cell	*lc, *lcchild;
 
+	if (depth > LAYOUT_V1_MAX_DEPTH)
+		return (NULL);
+
 	lc = layout_construct_cell(lcparent, layout);
 	if (lc == NULL)
 		return (NULL);
@@ -855,7 +895,7 @@ layout_construct_v1(struct layout_cell *lcparent, const char **layout)
 
 	do {
 		(*layout)++;
-		lcchild = layout_construct_v1(lc, layout);
+		lcchild = layout_construct_v1(lc, layout, depth + 1);
 		if (lcchild == NULL)
 			goto fail;
 		TAILQ_INSERT_TAIL(&lc->cells, lcchild, entry);
@@ -1068,7 +1108,8 @@ layout_construct(const char *input, struct layout_parse_ctx *pctx)
 			*pctx->cause = xstrdup("invalid layout checksum");
 			return (-1);
 		}
-		if ((pctx->root = layout_construct_v1(NULL, &input)) == NULL) {
+		pctx->root = layout_construct_v1(NULL, &input, 0);
+		if (pctx->root == NULL) {
 			*pctx->cause = xstrdup("invalid layout");
 			return (-1);
 		}

layout.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: layout.c,v 1.99 2026/09/09 07:03:39 nicm Exp $ */
+/* $OpenBSD: layout.c,v 1.101 2026/09/20 08:42:46 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -469,7 +469,6 @@ layout_fix_panes(struct window *w, struct window_pane *skip)
 					sx = PANE_MINIMUM;
 				else
 					sx = sx - sb_w - sb_pad;
-			wp->flags |= PANE_REDRAWSCROLLBAR;
 		}
 
 		window_pane_resize(wp, sx, sy);
@@ -477,8 +476,11 @@ layout_fix_panes(struct window *w, struct window_pane *skip)
 		if (wp->xoff != old_xoff ||
 		    wp->yoff != old_yoff ||
 		    wp->sx != old_sx ||
-		    wp->sy != old_sy)
+		    wp->sy != old_sy) {
+			if (window_pane_scrollbar_reserve(wp))
+				wp->flags |= PANE_REDRAWSCROLLBAR;
 			changed = 1;
+		}
 	}
 	if (changed)
 		redraw_invalidate_scene(w);
@@ -768,6 +770,49 @@ layout_free(struct window *w, int only_nodes)
 	layout_free_cell(w->layout_root, only_nodes);
 }
 
+/* Move and resize floating panes so they stay inside the window. */
+static void
+layout_clamp_floating_panes(struct window *w, u_int sx, u_int sy)
+{
+	struct window_pane	*wp;
+	struct layout_cell	*lc;
+	u_int			 pad, avail, csx, csy;
+
+	TAILQ_FOREACH(wp, &w->z_index, zentry) {
+		lc = wp->layout_cell;
+		if (lc == NULL || (~lc->flags & LAYOUT_CELL_FLOATING))
+			continue;
+		if (window_pane_get_pane_lines(wp) == PANE_LINES_NONE)
+			pad = 0;
+		else
+			pad = 1;
+
+		csx = lc->g.sx;
+		avail = (sx > 2 * pad) ? sx - 2 * pad : 0;
+		if (csx > avail)
+			csx = (avail > PANE_MINIMUM) ? avail : PANE_MINIMUM;
+		csy = lc->g.sy;
+		avail = (sy > 2 * pad) ? sy - 2 * pad : 0;
+		if (csy > avail)
+			csy = (avail > PANE_MINIMUM) ? avail : PANE_MINIMUM;
+		if (csx != lc->g.sx || csy != lc->g.sy)
+			layout_set_size(lc, csx, csy, lc->g.xoff, lc->g.yoff);
+
+		if (lc->g.xoff + lc->g.sx + pad > sx) {
+			if (lc->g.sx + 2 * pad >= sx)
+				lc->g.xoff = pad;
+			else
+				lc->g.xoff = sx - lc->g.sx - pad;
+		}
+		if (lc->g.yoff + lc->g.sy + pad > sy) {
+			if (lc->g.sy + 2 * pad >= sy)
+				lc->g.yoff = pad;
+			else
+				lc->g.yoff = sy - lc->g.sy - pad;
+		}
+	}
+}
+
 /* Resize the entire layout after window resize. */
 void
 layout_resize(struct window *w, u_int sx, u_int sy)
@@ -788,8 +833,11 @@ layout_resize(struct window *w, u_int sx, u_int sy)
 	 * out proportionately - this should leave the layout fitting the new
 	 * window size.
 	 */
-	if (lc->type == LAYOUT_WINDOWPANE && (lc->flags & LAYOUT_CELL_FLOATING))
+	if (lc->type == LAYOUT_WINDOWPANE && (lc->flags & LAYOUT_CELL_FLOATING)) {
+		layout_clamp_floating_panes(w, sx, sy);
+		layout_fix_panes(w, NULL);
 		return;
+	}
 	xchange = sx - lc->g.sx;
 	xlimit = layout_resize_check(w, lc, LAYOUT_LEFTRIGHT);
 	if (xchange < 0 && xchange < -xlimit)
@@ -819,6 +867,7 @@ layout_resize(struct window *w, u_int sx, u_int sy)
 
 	/* Fix cell offsets. */
 	layout_fix_offsets(w);
+	layout_clamp_floating_panes(w, sx, sy);
 	layout_fix_panes(w, NULL);
 }
 
@@ -1681,7 +1730,7 @@ layout_floating_args_parse(struct cmdq_item *item, struct args *args,
     enum pane_lines lines, struct window *w, struct layout_geometry *lg,
     char **cause)
 {
-	int	 sx, sy, ox, oy;
+	int	 sx, sy, ox, oy, pad;
 	char	*error = NULL;
 
 	sx = lg->sx == UINT_MAX ? w->sx / 2 : lg->sx;
@@ -1730,12 +1779,20 @@ layout_floating_args_parse(struct cmdq_item *item, struct args *args,
 		}
 	}
 
+	if (!window_has_floating_panes(w)) {
+		w->last_new_pane_x = 0;
+		w->last_new_pane_y = 0;
+	}
 	if (ox == INT_MAX) {
 		if (w->last_new_pane_x == 0)
 			ox = 4;
 		else {
+			if (lines != PANE_LINES_NONE)
+				pad = 1;
+			else
+				pad = 0;
 			ox = w->last_new_pane_x + 4;
-			if (w->last_new_pane_x > w->sx)
+			if (ox + sx + pad > (int)w->sx)
 				ox = 4;
 		}
 		w->last_new_pane_x = ox;
@@ -1746,8 +1803,12 @@ layout_floating_args_parse(struct cmdq_item *item, struct args *args,
 		if (w->last_new_pane_y == 0)
 			oy = 2;
 		else {
+			if (lines != PANE_LINES_NONE)
+				pad = 1;
+			else
+				pad = 0;
 			oy = w->last_new_pane_y + 2;
-			if (w->last_new_pane_y > w->sy)
+			if (oy + sy + pad > (int)w->sy)
 				oy = 2;
 		}
 		w->last_new_pane_y = oy;

menu.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: menu.c,v 1.70 2026/08/17 07:33:55 nicm Exp $ */
+/* $OpenBSD: menu.c,v 1.71 2026/09/21 12:14:32 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -51,6 +51,18 @@ struct menu_data {
 	void			*data;
 };
 
+void
+menu_get_size(struct menu *menu, enum box_lines lines, u_int *sx, u_int *sy)
+{
+	if (lines == BOX_LINES_NONE) {
+		*sx = menu->item_width + 2;
+		*sy = menu->count;
+	} else {
+		*sx = menu->width + 4;
+		*sy = menu->count + 2;
+	}
+}
+
 void
 menu_add_items(struct menu *menu, const struct menu_item *items,
     struct cmdq_item *qitem, struct client *c, struct cmd_find_state *fs)
@@ -142,6 +154,8 @@ menu_add_item(struct menu *menu, const struct menu_item *item,
 	width = format_width(new_item->name);
 	if (*new_item->name == '-')
 		width--;
+	if (width > menu->item_width)
+		menu->item_width = width;
 	if (width > menu->width)
 		menu->width = width;
 }
@@ -238,7 +252,7 @@ menu_update(struct menu_data *md)
 	screen_write_clearscreen(&ctx, 8);
 
 	if (md->border_lines != BOX_LINES_NONE) {
-		screen_write_box(&ctx, menu->width + 4, menu->count + 2,
+		screen_write_box(&ctx, menu_width(md), menu_height(md),
 		    md->border_lines, &md->border_style_gc, menu->title);
 	}
 
@@ -286,11 +300,13 @@ menu_destroy(struct window *w)
 void
 menu_get_cursor(struct menu_data *md, u_int *cx, u_int *cy)
 {
-	*cx = md->px + 2;
+	u_int	border = (md->border_lines != BOX_LINES_NONE);
+
+	*cx = md->px + 1 + border;
 	if (md->choice == -1)
 		*cy = md->py;
 	else
-		*cy = md->py + 1 + md->choice;
+		*cy = md->py + border + md->choice;
 }
 
 struct screen *
@@ -302,13 +318,19 @@ menu_screen(struct menu_data *md)
 u_int
 menu_width(struct menu_data *md)
 {
-	return (md->menu->width + 4);
+	u_int	sx, sy;
+
+	menu_get_size(md->menu, md->border_lines, &sx, &sy);
+	return (sx);
 }
 
 u_int
 menu_height(struct menu_data *md)
 {
-	return (md->menu->count + 2);
+	u_int	sx, sy;
+
+	menu_get_size(md->menu, md->border_lines, &sx, &sy);
+	return (sy);
 }
 
 u_int
@@ -338,6 +360,7 @@ menu_key(struct client *c, struct menu_data *md, struct key_event *event)
 	enum cmd_parse_status		 status;
 	char				*error;
 	key_code			 key;
+	u_int				 border;
 
 	if (KEYC_IS_MOUSE(event->key)) {
 		/*
@@ -353,10 +376,10 @@ menu_key(struct client *c, struct menu_data *md, struct key_event *event)
 				return (1);
 			return (0);
 		}
-		if (m->x < md->px ||
-		    m->x > md->px + 4 + menu->width ||
-		    m->y < md->py + 1 ||
-		    m->y > md->py + 1 + n - 1) {
+		border = (md->border_lines != BOX_LINES_NONE);
+		if (m->x < md->px || m->x >= md->px + menu_width(md) ||
+		    m->y < md->py + border ||
+		    m->y >= md->py + border + n) {
 			if (~md->flags & MENU_STAYOPEN) {
 				if (!move && MOUSE_RELEASE(m->b))
 					return (1);
@@ -379,7 +402,7 @@ menu_key(struct client *c, struct menu_data *md, struct key_event *event)
 			if (!MOUSE_WHEEL(m->b) && !MOUSE_DRAG(m->b))
 				goto chosen;
 		}
-		md->choice = m->y - (md->py + 1);
+		md->choice = m->y - (md->py + border);
 		if (md->choice != old)
 			server_redraw_window_menu(md->w);
 		return (0);
@@ -546,20 +569,16 @@ menu_resize(struct menu_data *md, struct window *w)
 
 	if (md == NULL)
 		return;
-
 	nx = md->px;
 	ny = md->py;
 
-	sx = md->menu->width + 4;
-	sy = md->menu->count + 2;
-
+	menu_get_size(md->menu, md->border_lines, &sx, &sy);
 	if (nx + sx > w->sx) {
 		if (w->sx <= sx)
 			nx = 0;
 		else
 			nx = w->sx - sx;
 	}
-
 	if (ny + sy > w->sy) {
 		if (w->sy <= sy)
 			ny = 0;
@@ -591,8 +610,9 @@ menu_display(struct menu *menu, int flags, int starting_choice,
 		w = fs->w;
 	o = w->options;
 
-	sx = menu->width + 4;
-	sy = menu->count + 2;
+	if (lines == BOX_LINES_DEFAULT)
+		lines = options_get_number(o, "menu-border-lines");
+	menu_get_size(menu, lines, &sx, &sy);
 	if (sx >= w->sx)
 		px = 0;
 	else if (px + sx > w->sx)
@@ -604,9 +624,6 @@ menu_display(struct menu *menu, int flags, int starting_choice,
 	w->menu_last_px = px;
 	w->menu_last_py = py;
 
-	if (lines == BOX_LINES_DEFAULT)
-		lines = options_get_number(o, "menu-border-lines");
-
 	md = xcalloc(1, sizeof *md);
 	md->w = w;
 	md->flags = flags;

mode-tree.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: mode-tree.c,v 1.101 2026/08/05 07:50:21 nicm Exp $ */
+/* $OpenBSD: mode-tree.c,v 1.102 2026/09/21 12:14:32 nicm Exp $ */
 
 /*
  * Copyright (c) 2017 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1375,12 +1375,14 @@ static void
 mode_tree_display_menu(struct mode_tree_data *mtd, struct client *c, u_int x,
     u_int y, int outside)
 {
+	struct window		*w = mtd->wp->window;
 	struct mode_tree_item	*mti;
 	struct menu		*menu;
 	const struct menu_item	*items;
 	struct mode_tree_menu	*mtm;
 	char			*title;
-	u_int			 line;
+	enum box_lines		 lines;
+	u_int			 line, sx, sy;
 
 	if (mtd->offset + y > mtd->line_size - 1)
 		line = mtd->current;
@@ -1405,14 +1407,17 @@ mode_tree_display_menu(struct mode_tree_data *mtd, struct client *c, u_int x,
 	mtm->line = line;
 	mtd->references++;
 
-	if (x >= (menu->width + 4) / 2)
-		x -= (menu->width + 4) / 2;
+	lines = options_get_number(w->options, "menu-border-lines");
+	menu_get_size(menu, lines, &sx, &sy);
+	if (x >= sx / 2)
+		x -= sx / 2;
 	else
 		x = 0;
 	x += mtd->wp->xoff;
 	y += mtd->wp->yoff;
-	if (menu_display(menu, 0, 0, NULL, x, y, c, BOX_LINES_DEFAULT, NULL,
-	    NULL, NULL, NULL, mode_tree_menu_callback, mtm) != 0) {
+
+	if (menu_display(menu, 0, 0, NULL, x, y, c, lines, NULL, NULL, NULL,
+	    NULL, mode_tree_menu_callback, mtm) != 0) {
 		mode_tree_remove_ref(mtd);
 		free(mtm);
 		menu_free(menu);

options-table.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: options-table.c,v 1.244 2026/09/01 12:49:49 nicm Exp $ */
+/* $OpenBSD: options-table.c,v 1.247 2026/09/21 10:22:31 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -76,9 +76,10 @@ static const char *options_table_pane_border_indicators_list[] = {
 	"off", "colour", "arrows", "both", NULL
 };
 static const char *options_table_pane_border_lines_list[] = {
-	"single", "double", "heavy", "simple", "number", "spaces", "none", NULL
+	"single", "double", "heavy", "simple", "number", "spaces", "none",
+	"rounded", NULL
 };
-static const char *options_table_popup_border_lines_list[] = {
+static const char *options_table_menu_border_lines_list[] = {
 	"single", "double", "heavy", "simple", "rounded", "padded", "none", NULL
 };
 static const char *options_table_set_clipboard_list[] = {
@@ -91,7 +92,7 @@ static const char *options_table_window_size_list[] = {
 	"largest", "smallest", "manual", "latest", NULL
 };
 static const char *options_table_remain_on_exit_list[] = {
-	"off", "on", "failed", "key", NULL
+	"off", "on", "failed", "key", "failed-key", NULL
 };
 static const char *options_table_destroy_unattached_list[] = {
 	"off", "on", "keep-last", "keep-group", NULL
@@ -492,7 +493,7 @@ const struct options_table_entry options_table[] = {
 	{ .name = "menu-border-lines",
 	  .type = OPTIONS_TABLE_CHOICE,
 	  .scope = OPTIONS_TABLE_WINDOW,
-	  .choices = options_table_popup_border_lines_list,
+	  .choices = options_table_menu_border_lines_list,
 	  .default_num = BOX_LINES_SINGLE,
 	  .text = "Type of characters used to draw menu border lines. Some of "
 		  "these are only supported on terminals with UTF-8 support."
@@ -1665,40 +1666,14 @@ const struct options_table_entry options_table[] = {
 	  .text = "Pane scrollbar position."
 	},
 
-	{ .name = "popup-style",
-	  .type = OPTIONS_TABLE_STRING,
-	  .scope = OPTIONS_TABLE_WINDOW,
-	  .default_str = "bg=themedarkgrey,fg=themewhite",
-	  .flags = OPTIONS_TABLE_IS_STYLE,
-	  .separator = ",",
-	  .text = "Default style of popups."
-	},
-
-	{ .name = "popup-border-style",
-	  .type = OPTIONS_TABLE_STRING,
-	  .scope = OPTIONS_TABLE_WINDOW,
-	  .default_str = "bg=themedarkgrey,fg=themelightgrey",
-	  .flags = OPTIONS_TABLE_IS_STYLE,
-	  .separator = ",",
-	  .text = "Default style of popup borders."
-	},
-
-	{ .name = "popup-border-lines",
-	  .type = OPTIONS_TABLE_CHOICE,
-	  .scope = OPTIONS_TABLE_WINDOW,
-	  .choices = options_table_popup_border_lines_list,
-	  .default_num = BOX_LINES_SINGLE,
-	  .text = "Type of characters used to draw popup border lines. Some of "
-		  "these are only supported on terminals with UTF-8 support."
-	},
-
 	{ .name = "remain-on-exit",
 	  .type = OPTIONS_TABLE_CHOICE,
 	  .scope = OPTIONS_TABLE_WINDOW|OPTIONS_TABLE_PANE,
 	  .choices = options_table_remain_on_exit_list,
 	  .default_num = 0,
 	  .text = "Whether panes should remain ('on'), remain until a key is "
-		  "pressed ('key') or be automatically killed ('off' or "
+		  "pressed after any exit ('key') or after a failure "
+		  "('failed-key'), or be automatically killed ('off' or "
 		  "'failed') when the program inside exits."
 	},
 

popup.c

@@ -1,661 +0,0 @@
-/* $OpenBSD: popup.c,v 1.77 2026/08/28 08:02:16 nicm Exp $ */
-
-/*
- * Copyright (c) 2020 Nicholas Marriott <nicholas.marriott@gmail.com>
- *
- * Permission to use, copy, modify, and distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
- * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
- * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- */
-
-#include <sys/types.h>
-#include <sys/wait.h>
-
-#include <signal.h>
-#include <stdlib.h>
-#include <string.h>
-#include <unistd.h>
-
-#include "tmux.h"
-
-struct popup_data {
-	struct client		 *c;
-	struct cmdq_item	 *item;
-	int			  flags;
-	char			 *title;
-
-	char			 *style;
-	char			 *border_style;
-	struct grid_cell	  border_cell;
-	enum box_lines		  border_lines;
-
-	struct screen		  s;
-	struct grid_cell	  defaults;
-	struct colour_palette	  palette;
-
-	struct visible_ranges	  r;
-
-	struct job		 *job;
-	struct input_ctx	 *ictx;
-	int			  status;
-	popup_close_cb		  cb;
-	void			 *arg;
-
-	int			  close;
-
-	/* Current position and size. */
-	u_int			  px;
-	u_int			  py;
-	u_int			  sx;
-	u_int			  sy;
-
-	/* Preferred position and size. */
-	u_int			  ppx;
-	u_int			  ppy;
-	u_int			  psx;
-	u_int			  psy;
-
-	enum { OFF, MOVE, SIZE }  dragging;
-	u_int			  dx;
-	u_int			  dy;
-
-	u_int			  lx;
-	u_int			  ly;
-	u_int			  lb;
-};
-
-static void
-popup_free(struct popup_data *pd)
-{
-	server_client_unref(pd->c);
-
-	if (pd->job != NULL)
-		job_free(pd->job);
-	if (pd->ictx != NULL)
-		input_free(pd->ictx);
-
-	free(pd->r.ranges);
-	screen_free(&pd->s);
-	colour_palette_free(&pd->palette);
-
-	free(pd->title);
-	free(pd->style);
-	free(pd->border_style);
-	free(pd);
-}
-
-static void
-popup_reapply_styles(struct popup_data *pd)
-{
-	struct client		*c = pd->c;
-	struct session		*s = c->session;
-	struct options		*o;
-	struct format_tree	*ft;
-	struct style		 sytmp;
-
-	if (s == NULL)
-		return;
-	o = s->curw->window->options;
-
-	ft = format_create_defaults(NULL, c, s, s->curw, NULL);
-
-	/* Reapply popup style from options. */
-	memcpy(&pd->defaults, &grid_default_cell, sizeof pd->defaults);
-	style_apply(&pd->defaults, o, "popup-style", ft);
-	if (pd->style != NULL) {
-		style_set(&sytmp, &grid_default_cell);
-		if (style_parse(&sytmp, &pd->defaults, pd->style) == 0) {
-			pd->defaults.fg = sytmp.gc.fg;
-			pd->defaults.bg = sytmp.gc.bg;
-		}
-	}
-	pd->defaults.attr = 0;
-
-	/* Reapply border style from options. */
-	memcpy(&pd->border_cell, &grid_default_cell, sizeof pd->border_cell);
-	style_apply(&pd->border_cell, o, "popup-border-style", ft);
-	if (pd->border_style != NULL) {
-		style_set(&sytmp, &grid_default_cell);
-		if (style_parse(&sytmp, &pd->border_cell,
-		    pd->border_style) == 0) {
-			pd->border_cell.fg = sytmp.gc.fg;
-			pd->border_cell.bg = sytmp.gc.bg;
-		}
-	}
-	pd->border_cell.attr = 0;
-
-	format_free(ft);
-}
-
-static void
-popup_redraw_cb(const struct tty_ctx *ttyctx)
-{
-	struct popup_data	*pd = ttyctx->arg;
-
-	pd->c->flags |= CLIENT_REDRAWOVERLAY;
-}
-
-static int
-popup_set_client_cb(struct tty_ctx *ttyctx, struct client *c)
-{
-	struct popup_data	*pd = ttyctx->arg;
-
-	if (c != pd->c)
-		return (0);
-	if (pd->c->flags & CLIENT_REDRAWOVERLAY)
-		return (0);
-
-	ttyctx->wox = 0;
-	ttyctx->woy = 0;
-	ttyctx->wsx = c->tty.sx;
-	ttyctx->wsy = c->tty.sy;
-
-	if (pd->border_lines == BOX_LINES_NONE) {
-		ttyctx->xoff = ttyctx->rxoff = pd->px;
-		ttyctx->yoff = ttyctx->ryoff = pd->py;
-	} else {
-		ttyctx->xoff = ttyctx->rxoff = pd->px + 1;
-		ttyctx->yoff = ttyctx->ryoff = pd->py + 1;
-	}
-
-	return (1);
-}
-
-static void
-popup_init_ctx_cb(struct screen_write_ctx *ctx, struct tty_ctx *ttyctx)
-{
-	struct popup_data	*pd = ctx->arg;
-
-	memcpy(&ttyctx->defaults, &pd->defaults, sizeof ttyctx->defaults);
-	ttyctx->flags &= ~TTY_CTX_WINDOW_BIGGER;
-	ttyctx->style_ctx.defaults = &ttyctx->defaults;
-	ttyctx->style_ctx.palette = &pd->palette;
-	ttyctx->redraw_cb = popup_redraw_cb;
-	ttyctx->set_client_cb = popup_set_client_cb;
-	ttyctx->arg = pd;
-}
-
-static struct screen *
-popup_mode_cb(__unused struct client *c, void *data, u_int *cx, u_int *cy)
-{
-	struct popup_data	*pd = data;
-
-	if (pd->border_lines == BOX_LINES_NONE) {
-		*cx = pd->px + pd->s.cx;
-		*cy = pd->py + pd->s.cy;
-	} else {
-		*cx = pd->px + 1 + pd->s.cx;
-		*cy = pd->py + 1 + pd->s.cy;
-	}
-	return (&pd->s);
-}
-
-/* Return parts of the input range which are not obstructed by the popup. */
-static struct visible_ranges *
-popup_check_cb(__unused struct client* c, void *data, u_int px, u_int py,
-    u_int nx)
-{
-	struct popup_data	*pd = data;
-	struct visible_ranges	*r = &pd->r;
-
-	server_client_overlay_range(pd->px, pd->py, pd->sx, pd->sy, px, py, nx,
-	    r);
-	return (r);
-}
-
-static void
-popup_draw_cb(struct client *c, void *data)
-{
-	struct popup_data	*pd = data;
-	struct tty		*tty = &c->tty;
-	struct screen		 s;
-	struct screen_write_ctx	 ctx;
-	u_int			 i, px = pd->px, py = pd->py;
-	struct grid_cell	 defaults;
-	struct tty_style_ctx	 style_ctx;
-
-	popup_reapply_styles(pd);
-
-	screen_init(&s, pd->sx, pd->sy, 0);
-	if (pd->s.hyperlinks != NULL) {
-		hyperlinks_free(s.hyperlinks);
-		s.hyperlinks = hyperlinks_copy(pd->s.hyperlinks);
-	}
-	screen_write_start(&ctx, &s);
-	screen_write_clearscreen(&ctx, 8);
-
-	if (pd->border_lines == BOX_LINES_NONE) {
-		screen_write_cursormove(&ctx, 0, 0, 0);
-		screen_write_fast_copy(&ctx, &pd->s, 0, 0, pd->sx, pd->sy);
-	} else if (pd->sx > 2 && pd->sy > 2) {
-		screen_write_box(&ctx, pd->sx, pd->sy, pd->border_lines,
-		    &pd->border_cell, pd->title);
-		screen_write_cursormove(&ctx, 1, 1, 0);
-		screen_write_fast_copy(&ctx, &pd->s, 0, 0, pd->sx - 2,
-		    pd->sy - 2);
-	}
-	screen_write_stop(&ctx);
-
-	memcpy(&defaults, &pd->defaults, sizeof defaults);
-	if (defaults.fg == 8)
-		defaults.fg = pd->palette.fg;
-	if (defaults.bg == 8)
-		defaults.bg = pd->palette.bg;
-	style_ctx.defaults = &defaults;
-	style_ctx.palette = &pd->palette;
-	style_ctx.dim = 0;
-	style_ctx.hyperlinks = s.hyperlinks;
-
-	c->overlay_check = NULL;
-	c->overlay_data = NULL;
-	for (i = 0; i < pd->sy; i++)
-		tty_draw_line(tty, &s, 0, i, pd->sx, px, py + i, &style_ctx);
-	screen_free(&s);
-	c->overlay_check = popup_check_cb;
-	c->overlay_data = pd;
-}
-
-static void
-popup_free_cb(__unused struct client *c, void *data)
-{
-	struct popup_data	*pd = data;
-	struct cmdq_item	*item = pd->item;
-
-	if (pd->cb != NULL)
-		pd->cb(pd->status, pd->arg);
-
-	if (item != NULL) {
-		if (cmdq_get_client(item) != NULL &&
-		    cmdq_get_client(item)->session == NULL)
-			cmdq_get_client(item)->retval = pd->status;
-		cmdq_continue(item);
-	}
-
-	popup_free(pd);
-}
-
-static void
-popup_resize_cb(__unused struct client *c, void *data)
-{
-	struct popup_data	*pd = data;
-	struct tty		*tty = &c->tty;
-
-	if (pd == NULL)
-		return;
-
-	/* Adjust position and size. */
-	if (pd->psy > tty->sy)
-		pd->sy = tty->sy;
-	else
-		pd->sy = pd->psy;
-	if (pd->psx > tty->sx)
-		pd->sx = tty->sx;
-	else
-		pd->sx = pd->psx;
-	if (pd->ppy + pd->sy > tty->sy)
-		pd->py = tty->sy - pd->sy;
-	else
-		pd->py = pd->ppy;
-	if (pd->ppx + pd->sx > tty->sx)
-		pd->px = tty->sx - pd->sx;
-	else
-		pd->px = pd->ppx;
-
-	/* Avoid zero size screens. */
-	if (pd->border_lines == BOX_LINES_NONE) {
-		screen_resize(&pd->s, pd->sx, pd->sy, 0);
-		if (pd->job != NULL)
-			job_resize(pd->job, pd->sx, pd->sy );
-	} else if (pd->sx > 2 && pd->sy > 2) {
-		screen_resize(&pd->s, pd->sx - 2, pd->sy - 2, 0);
-		if (pd->job != NULL)
-			job_resize(pd->job, pd->sx - 2, pd->sy - 2);
-	}
-}
-
-static void
-popup_handle_drag(struct client *c, struct popup_data *pd,
-    struct mouse_event *m)
-{
-	u_int	px, py;
-
-	if (!MOUSE_DRAG(m->b))
-		pd->dragging = OFF;
-	else if (pd->dragging == MOVE) {
-		if (m->x < pd->dx)
-			px = 0;
-		else if (m->x - pd->dx + pd->sx > c->tty.sx)
-			px = c->tty.sx - pd->sx;
-		else
-			px = m->x - pd->dx;
-		if (m->y < pd->dy)
-			py = 0;
-		else if (m->y - pd->dy + pd->sy > c->tty.sy)
-			py = c->tty.sy - pd->sy;
-		else
-			py = m->y - pd->dy;
-		pd->px = px;
-		pd->py = py;
-		pd->dx = m->x - pd->px;
-		pd->dy = m->y - pd->py;
-		pd->ppx = px;
-		pd->ppy = py;
-		server_redraw_client(c);
-	} else if (pd->dragging == SIZE) {
-		if (pd->border_lines == BOX_LINES_NONE) {
-			if (m->x < pd->px + 1)
-				return;
-			if (m->y < pd->py + 1)
-				return;
-		} else {
-			if (m->x < pd->px + 3)
-				return;
-			if (m->y < pd->py + 3)
-				return;
-		}
-		pd->sx = m->x - pd->px;
-		pd->sy = m->y - pd->py;
-		pd->psx = pd->sx;
-		pd->psy = pd->sy;
-
-		if (pd->border_lines == BOX_LINES_NONE) {
-			screen_resize(&pd->s, pd->sx, pd->sy, 0);
-			if (pd->job != NULL)
-				job_resize(pd->job, pd->sx, pd->sy);
-		} else {
-			screen_resize(&pd->s, pd->sx - 2, pd->sy - 2, 0);
-			if (pd->job != NULL)
-				job_resize(pd->job, pd->sx - 2, pd->sy - 2);
-		}
-		server_redraw_client(c);
-	}
-}
-
-static int
-popup_key_cb(struct client *c, void *data, struct key_event *event)
-{
-	struct popup_data	*pd = data;
-	struct mouse_event	*m = &event->m;
-	const char		*buf;
-	size_t			 len;
-	u_int			 px, py;
-	enum { NONE, LEFT, RIGHT, TOP, BOTTOM } border = NONE;
-
-	if (KEYC_IS_MOUSE(event->key)) {
-		if (pd->dragging != OFF) {
-			popup_handle_drag(c, pd, m);
-			goto out;
-		}
-		if (m->x < pd->px ||
-		    m->x > pd->px + pd->sx - 1 ||
-		    m->y < pd->py ||
-		    m->y > pd->py + pd->sy - 1) {
-			return (0);
-		}
-		if (pd->border_lines != BOX_LINES_NONE) {
-			if (m->x == pd->px)
-				border = LEFT;
-			else if (m->x == pd->px + pd->sx - 1)
-				border = RIGHT;
-			else if (m->y == pd->py)
-				border = TOP;
-			else if (m->y == pd->py + pd->sy - 1)
-				border = BOTTOM;
-		}
-		if ((m->b & MOUSE_MASK_MODIFIERS) == 0 &&
-		    MOUSE_BUTTONS(m->b) == MOUSE_BUTTON_3 &&
-		    (border == LEFT || border == TOP))
-			goto out;
-		if (((m->b & MOUSE_MASK_MODIFIERS) == MOUSE_MASK_META) ||
-		    (border != NONE && !MOUSE_DRAG(m->lb))) {
-			if (!MOUSE_DRAG(m->b))
-				goto out;
-			if (MOUSE_BUTTONS(m->lb) == MOUSE_BUTTON_1)
-				pd->dragging = MOVE;
-			else if (MOUSE_BUTTONS(m->lb) == MOUSE_BUTTON_3)
-				pd->dragging = SIZE;
-			pd->dx = m->lx - pd->px;
-			pd->dy = m->ly - pd->py;
-			goto out;
-		}
-	}
-	if ((((pd->flags & (POPUP_CLOSEEXIT|POPUP_CLOSEEXITZERO)) == 0) ||
-	    pd->job == NULL) &&
-	    (event->key == '\033' || event->key == ('c'|KEYC_CTRL)))
-		return (1);
-	if (pd->job == NULL && (pd->flags & POPUP_CLOSEANYKEY) &&
-	    !KEYC_IS_MOUSE(event->key) && !KEYC_IS_PASTE(event->key))
-		return (1);
-	if (pd->job != NULL) {
-		if (KEYC_IS_MOUSE(event->key)) {
-			/* Must be inside, checked already. */
-			if (pd->border_lines == BOX_LINES_NONE) {
-				px = m->x - pd->px;
-				py = m->y - pd->py;
-			} else {
-				px = m->x - pd->px - 1;
-				py = m->y - pd->py - 1;
-			}
-			if (!input_key_get_mouse(&pd->s, m, px, py, &buf, &len))
-				return (0);
-			bufferevent_write(job_get_event(pd->job), buf, len);
-			return (0);
-		}
-		input_key(&pd->s, job_get_event(pd->job), event->key);
-	}
-	return (0);
-
-out:
-	pd->lx = m->x;
-	pd->ly = m->y;
-	pd->lb = m->b;
-	return (0);
-}
-
-static void
-popup_job_update_cb(struct job *job)
-{
-	struct popup_data	*pd = job_get_data(job);
-	struct evbuffer		*evb = job_get_event(job)->input;
-	struct client		*c = pd->c;
-	struct screen		*s = &pd->s;
-	void			*data = EVBUFFER_DATA(evb);
-	size_t			 size = EVBUFFER_LENGTH(evb);
-
-	if (size == 0)
-		return;
-
-	c->overlay_check = NULL;
-	c->overlay_data = NULL;
-	input_parse_screen(pd->ictx, s, popup_init_ctx_cb, pd, data, size);
-	c->overlay_check = popup_check_cb;
-	c->overlay_data = pd;
-
-	evbuffer_drain(evb, size);
-}
-
-static void
-popup_job_complete_cb(struct job *job)
-{
-	struct popup_data	*pd = job_get_data(job);
-	int			 status;
-
-	status = job_get_status(pd->job);
-	if (WIFEXITED(status))
-		pd->status = WEXITSTATUS(status);
-	else if (WIFSIGNALED(status))
-		pd->status = WTERMSIG(status);
-	else
-		pd->status = 0;
-	pd->job = NULL;
-
-	if ((pd->flags & POPUP_CLOSEEXIT) ||
-	    ((pd->flags & POPUP_CLOSEEXITZERO) && pd->status == 0))
-		server_client_clear_overlay(pd->c);
-}
-
-int
-popup_present(struct client *c)
-{
-	return (c->overlay_draw == popup_draw_cb);
-}
-
-int
-popup_modify(struct client *c, const char *title, const char *style,
-	const char *border_style, enum box_lines lines, int flags)
-{
-	struct popup_data		*pd = c->overlay_data;
-	struct style		sytmp;
-
-	if (title != NULL) {
-		if (pd->title != NULL)
-			free(pd->title);
-		pd->title = xstrdup(title);
-	}
-	if (border_style != NULL) {
-		free(pd->border_style);
-		pd->border_style = xstrdup(border_style);
-		style_set(&sytmp, &pd->border_cell);
-		if (style_parse(&sytmp, &pd->border_cell, border_style) == 0) {
-			pd->border_cell.fg = sytmp.gc.fg;
-			pd->border_cell.bg = sytmp.gc.bg;
-		}
-	}
-	if (style != NULL) {
-		free(pd->style);
-		pd->style = xstrdup(style);
-		style_set(&sytmp, &pd->defaults);
-		if (style_parse(&sytmp, &pd->defaults, style) == 0) {
-			pd->defaults.fg = sytmp.gc.fg;
-			pd->defaults.bg = sytmp.gc.bg;
-		}
-	}
-	if (lines != BOX_LINES_DEFAULT) {
-		if (lines == BOX_LINES_NONE && pd->border_lines != lines) {
-			screen_resize(&pd->s, pd->sx, pd->sy, 1);
-			job_resize(pd->job, pd->sx, pd->sy);
-		} else if (pd->border_lines == BOX_LINES_NONE &&
-		    pd->border_lines != lines) {
-			screen_resize(&pd->s, pd->sx - 2, pd->sy - 2, 1);
-			job_resize(pd->job, pd->sx - 2, pd->sy - 2);
-		}
-		pd->border_lines = lines;
-		tty_resize(&c->tty);
-	}
-	if (flags != -1)
-		pd->flags = flags;
-
-	server_redraw_client(c);
-	return (0);
-}
-
-int
-popup_display(int flags, enum box_lines lines, struct cmdq_item *item, u_int px,
-    u_int py, u_int sx, u_int sy, struct environ *env, const char *shellcmd,
-    int argc, char **argv, const char *cwd, const char *title, struct client *c,
-    struct session *s, const char *style, const char *border_style,
-    popup_close_cb cb, void *arg)
-{
-	struct popup_data	*pd;
-	u_int			 jx, jy;
-	struct options		*o;
-	struct style		 sytmp;
-
-	if (s != NULL)
-		o = s->curw->window->options;
-	else
-		o = c->session->curw->window->options;
-
-	if (lines == BOX_LINES_DEFAULT)
-		lines = options_get_number(o, "popup-border-lines");
-	if (lines == BOX_LINES_NONE) {
-		if (sx < 1 || sy < 1)
-			return (-1);
-		jx = sx;
-		jy = sy;
-	} else {
-		if (sx < 3 || sy < 3)
-			return (-1);
-		jx = sx - 2;
-		jy = sy - 2;
-	}
-	if (c->tty.sx < sx || c->tty.sy < sy)
-		return (-1);
-
-	pd = xcalloc(1, sizeof *pd);
-	pd->item = item;
-	pd->flags = flags;
-
-	if (title != NULL)
-		pd->title = xstrdup(title);
-	if (style != NULL)
-		pd->style = xstrdup(style);
-	if (border_style != NULL)
-		pd->border_style = xstrdup(border_style);
-
-	pd->c = c;
-	pd->c->references++;
-
-	pd->cb = cb;
-	pd->arg = arg;
-	pd->status = 128 + SIGHUP;
-
-	pd->border_lines = lines;
-	memcpy(&pd->border_cell, &grid_default_cell, sizeof pd->border_cell);
-	style_apply(&pd->border_cell, o, "popup-border-style", NULL);
-	if (border_style != NULL) {
-		style_set(&sytmp, &grid_default_cell);
-		if (style_parse(&sytmp, &pd->border_cell, border_style) == 0) {
-			pd->border_cell.fg = sytmp.gc.fg;
-			pd->border_cell.bg = sytmp.gc.bg;
-		}
-	}
-	pd->border_cell.attr = 0;
-
-	screen_init(&pd->s, jx, jy, 0);
-	screen_set_default_cursor(&pd->s, global_w_options);
-	colour_palette_init(&pd->palette);
-	colour_palette_from_option(&pd->palette, global_w_options);
-
-	memcpy(&pd->defaults, &grid_default_cell, sizeof pd->defaults);
-	style_apply(&pd->defaults, o, "popup-style", NULL);
-	if (style != NULL) {
-		style_set(&sytmp, &grid_default_cell);
-		if (style_parse(&sytmp, &pd->defaults, style) == 0) {
-			pd->defaults.fg = sytmp.gc.fg;
-			pd->defaults.bg = sytmp.gc.bg;
-		}
-	}
-	pd->defaults.attr = 0;
-
-	pd->px = px;
-	pd->py = py;
-	pd->sx = sx;
-	pd->sy = sy;
-
-	pd->ppx = px;
-	pd->ppy = py;
-	pd->psx = sx;
-	pd->psy = sy;
-
-	pd->job = job_run(shellcmd, argc, argv, env, s, cwd,
-	    popup_job_update_cb, popup_job_complete_cb, NULL, pd,
-	    JOB_NOWAIT|JOB_PTY|JOB_KEEPWRITE|JOB_DEFAULTSHELL, jx, jy);
-	if (pd->job == NULL) {
-		popup_free(pd);
-		return (-1);
-	}
-	pd->ictx = input_init(NULL, job_get_event(pd->job), &pd->palette, c);
-
-	server_client_set_overlay(c, 0, popup_check_cb, popup_mode_cb,
-	    popup_draw_cb, popup_key_cb, popup_free_cb, popup_resize_cb, pd);
-	return (0);
-}

regress/Makefile

@@ -1,33 +1,17 @@
 TESTS!= echo *.sh
 LOGDIR=logs
 
-.PHONY: all
-.NOTPARALLEL: all
+.PHONY: all prepare $(TESTS)
 
-all:
-	@mkdir -p "$(LOGDIR)"; \
-	rm -f "$(LOGDIR)"/*.log; \
-	failed=0; failures=; \
+all: prepare $(TESTS)
+	@failed=0; failures=; \
 	for test in $(TESTS); do \
 		base=$${test##*/}; \
 		log="$(LOGDIR)/$${base%.sh}.log"; \
-		rm -f "$$log"; \
-		printf '%-40s ' "$$test"; \
-		start=$$(date +%s); \
-		env -i LC_CTYPE=C.UTF-8 MallocNanoZone=0 \
-		    sh -x "$$test" >"$$log" 2>&1; \
-		if [ $$? -eq 0 ]; then \
-			end=$$(date +%s); \
-			rm -f "$$log"; \
-			echo "PASS ($$((end - start))s)"; \
-		else \
-			end=$$(date +%s); \
-			echo "FAIL ($$((end - start))s)"; \
-			echo " log: $$log"; \
+		if [ -f "$$log" ]; then \
 			failed=1; \
 			failures="$$failures $$test"; \
 		fi; \
-		sleep 1; \
 	done; \
 	if [ "$$failed" -ne 0 ]; then \
 		echo; \
@@ -39,3 +23,22 @@ all:
 		rmdir "$(LOGDIR)" 2>/dev/null || true; \
 	fi; \
 	exit $$failed
+
+prepare:
+	@mkdir -p "$(LOGDIR)"
+	@rm -f "$(LOGDIR)"/*.log
+
+$(TESTS): prepare
+	@base="$@"; base=$${base##*/}; \
+	log="$(LOGDIR)/$${base%.sh}.log"; \
+	start=$$(date +%s); \
+	if env -i LC_CTYPE=C.UTF-8 MallocNanoZone=0 \
+	    sh -x "$@" >"$$log" 2>&1; then \
+		end=$$(date +%s); \
+		rm -f "$$log"; \
+		printf '%-40s PASS (%ss)\n' "$@" "$$((end - start))"; \
+	else \
+		end=$$(date +%s); \
+		printf '%-40s FAIL (%ss)\n log: %s\n' \
+		    "$@" "$$((end - start))" "$$log"; \
+	fi

regress/alerts.sh

@@ -2,8 +2,9 @@
 
 # monitor-activity, monitor-bell and monitor-silence: both the
 # alert-activity, alert-bell and alert-silence hooks and the winlink alert
-# flags (window_activity_flag, window_bell_flag, window_silence_flag and
-# the #, !, ~ characters in window_flags). The sessions are detached so
+# flags (window_activity_flag, window_bell_flag, window_silence_flag,
+# their session equivalents and the #, !, ~ characters in window_flags).
+# The sessions are detached so
 # alert flags are set even on the current window; the *-action options
 # still decide whether the hooks fire. Panes run cat: activity is
 # generated by the tty echo of send-keys and a bell by sending a BEL and
@@ -111,6 +112,24 @@ flags_have()
 	esac
 }
 
+assert_session_flag()
+{
+	flag="#{session_${1}_flag}"
+	expected=$2
+
+	# Only mon exists here. Check both window contexts and list-sessions.
+	for target in mon:w0 "mon:$3"; do
+		value=$($TMUX display -pt "$target" "$flag") ||
+			fail "display $flag failed"
+		[ "$value" = "$expected" ] ||
+			fail "expected $flag for $target to be '$expected' but got '$value'"
+	done
+	value=$($TMUX list-sessions -F "$flag") ||
+		fail "list-sessions $flag failed"
+	[ "$value" = "$expected" ] ||
+		fail "expected list-sessions $flag to be '$expected' but got '$value'"
+}
+
 flags_lack()
 {
 	target=$1
@@ -150,10 +169,12 @@ $TMUX set-hook -g alert-silence \
 # alert-bell and sets the bell flag, shown as ! in window_flags.
 $TMUX neww -d -t mon: -n bellw cat || fail "new-window bellw failed"
 assert_fmt_unchanged mon:bellw '#{window_bell_flag}' 0
+assert_session_flag bell 0 bellw
 flags_lack mon:bellw '!'
 bell mon:bellw
 wait_for @log '|alert-bell:mon:bellw'
 wait_for_fmt mon:bellw '#{window_bell_flag}' 1
+assert_session_flag bell 1 bellw
 flags_have mon:bellw '!'
 
 # Bells are not deduplicated: a second bell fires the hook again even
@@ -164,6 +185,7 @@ wait_for @log '|alert-bell:mon:bellw|alert-bell:mon:bellw'
 # Selecting the window clears the alert flags.
 $TMUX selectw -t mon:bellw || fail "select-window bellw failed"
 wait_for_fmt mon:bellw '#{window_bell_flag}' 0
+assert_session_flag bell 0 bellw
 flags_lack mon:bellw '!'
 $TMUX selectw -t mon:w0 || fail "select-window w0 failed"
 
@@ -173,6 +195,7 @@ $TMUX set -g @log '' || fail "reset @log failed"
 bell mon:w0
 wait_for @log '|alert-bell:mon:w0'
 wait_for_fmt mon:w0 '#{window_bell_flag}' 1
+assert_session_flag bell 1 bellw
 $TMUX selectw -t mon:bellw || fail "select-window bellw failed"
 $TMUX selectw -t mon:w0 || fail "select-window w0 failed"
 wait_for_fmt mon:w0 '#{window_bell_flag}' 0
@@ -199,6 +222,7 @@ $TMUX neww -d -t mon: -n actw cat || fail "new-window actw failed"
 $TMUX set -g @log '' || fail "reset @log failed"
 activity mon:actw
 assert_fmt_unchanged mon:actw '#{window_activity_flag}' 0
+assert_session_flag activity 0 actw
 assert_unchanged @log ''
 
 # With monitor-activity on, output fires alert-activity and sets the
@@ -208,6 +232,7 @@ $TMUX set -wt mon:actw monitor-activity on ||
 activity mon:actw
 wait_for @log '|alert-activity:mon:actw'
 wait_for_fmt mon:actw '#{window_activity_flag}' 1
+assert_session_flag activity 1 actw
 flags_have mon:actw '#'
 
 # While the flag is set further activity does not fire the hook again.
@@ -234,6 +259,7 @@ exec 3>"$OUT/fifo"
 wait_for_fmt mon: '#{session_attached}' 1
 $TMUX selectw -t mon:actw || fail "select-window actw failed"
 wait_for_fmt mon:actw '#{window_activity_flag}' 0
+assert_session_flag activity 0 actw
 flags_lack mon:actw '#'
 $TMUX selectw -t mon:w0 || fail "select-window w0 failed"
 exec 3>&-
@@ -250,6 +276,7 @@ $TMUX set -wt mon:w0 monitor-activity on ||
 $TMUX set -g @log '' || fail "reset @log failed"
 activity mon:w0
 wait_for_fmt mon:w0 '#{window_activity_flag}' 1
+assert_session_flag activity 1 actw
 assert_unchanged @log ''
 $TMUX set -wut mon:w0 monitor-activity ||
 	fail "unset monitor-activity w0 failed"
@@ -273,16 +300,19 @@ $TMUX selectw -t mon:w0 || fail "select-window w0 failed"
 # running.
 $TMUX neww -d -t mon: -n silw cat || fail "new-window silw failed"
 assert_fmt_unchanged mon:silw '#{window_silence_flag}' 0
+assert_session_flag silence 0 silw
 $TMUX set -g @log '' || fail "reset @log failed"
 $TMUX set -wt mon:silw monitor-silence 1 || fail "set monitor-silence failed"
 wait_for @log '|alert-silence:mon:silw'
 wait_for_fmt mon:silw '#{window_silence_flag}' 1
+assert_session_flag silence 1 silw
 flags_have mon:silw '~'
 assert_unchanged @log '|alert-silence:mon:silw'
 $TMUX set -wt mon:silw monitor-silence 0 ||
 	fail "reset monitor-silence failed"
 $TMUX selectw -t mon:silw || fail "select-window silw failed"
 wait_for_fmt mon:silw '#{window_silence_flag}' 0
+assert_session_flag silence 0 silw
 flags_lack mon:silw '~'
 $TMUX selectw -t mon:w0 || fail "select-window w0 failed"
 

regress/attach-session-redraw.sh

@@ -0,0 +1,79 @@
+#!/bin/sh
+
+# Selecting a pane with attach-session from an already attached client must
+# redraw pane contents when window-style and window-active-style differ.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lattach-redraw-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lattach-redraw-outer-$$ -f/dev/null"
+BEFORE=$DIR/before
+AFTER=$DIR/after
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+LEFT=$($INNER new-session -dPF '#{pane_id}' -s inner -x 40 -y 8 \
+    "printf 'LEFT'; exec sleep 100") || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g default-terminal screen || exit 1
+$INNER split-window -h -t "$LEFT" "printf 'RIGHT'; exec sleep 100" || exit 1
+$INNER set-option -w -t "$LEFT" window-style bg=red || exit 1
+$INNER set-option -w -t "$LEFT" window-active-style bg=blue || exit 1
+$INNER bind-key -n x attach-session -t "$LEFT" || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 8 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lattach-redraw-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_client
+sleep 1
+$OUTER send-keys -t outer:0.0 x || exit 1
+sleep 1
+[ "$($INNER display-message -p -t inner '#{pane_id}')" = "$LEFT" ] ||
+    fail "attach-session did not select the target pane"
+$OUTER capture-pane -pe -t outer:0.0 >"$BEFORE" || exit 1
+
+# A forced redraw produces the correct scene. It must be identical to the
+# scene drawn immediately by attach-session.
+$INNER refresh-client -t "$CLIENT" || exit 1
+sleep 1
+$OUTER capture-pane -pe -t outer:0.0 >"$AFTER" || exit 1
+cmp -s "$BEFORE" "$AFTER" ||
+    fail "attach-session left stale active/inactive pane styles"
+
+exit 0

regress/check-names.sh

@@ -5,6 +5,15 @@
 PATH=/bin:/usr/bin
 TERM=screen
 
+# The pane's shell must not be the user's own interactive shell: a custom
+# PS1/PROMPT_COMMAND that sets the terminal title (as many do, for tmux/xterm
+# TERM types) would redraw over the titles this test sets and checks on
+# every prompt, regardless of how long it waits first.
+shell=
+if command -v bash >/dev/null 2>&1; then
+	shell='bash --noprofile --norc +o history'
+fi
+
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
 TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
 $TMUX kill-server 2>/dev/null
@@ -30,7 +39,7 @@ must_equal()
 	[ "$got" = "$want" ] || fail "got '$got', expected '$want'"
 }
 
-$TMUX new-session -d -x 80 -y 24 || exit 1
+$TMUX new-session -d -x 80 -y 24 -- $shell || exit 1
 $TMUX set-option -qg allow-set-title on || exit 1
 $TMUX set-option -qg allow-rename on || exit 1
 $TMUX set-option -qg automatic-rename off || exit 1

regress/codepoint-widths.sh

@@ -0,0 +1,53 @@
+#!/bin/sh
+
+# Width cache ranges must include their endpoint without overflowing wchar_t.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+SERVER=
+WATCHDOG=
+
+cleanup()
+{
+	if [ -n "$WATCHDOG" ]; then
+		kill "$WATCHDOG" 2>/dev/null
+		wait "$WATCHDOG" 2>/dev/null
+	fi
+	[ -n "$SERVER" ] && kill -9 "$SERVER" 2>/dev/null
+}
+trap cleanup 0
+trap 'exit 1' 1 2 15
+
+$TMUX new-session -d 'exec sleep 60' || exit 1
+SERVER=$($TMUX display-message -p '#{pid}') || exit 1
+
+# kill-server cannot stop a server stuck rebuilding the width cache.
+(
+	sleep 5
+	kill -9 "$SERVER" 2>/dev/null
+) &
+WATCHDOG=$!
+
+$TMUX set -g codepoint-widths 'U+1F600=2' || exit 1
+
+# Cover both signed and unsigned 32-bit wchar_t. Values above WCHAR_MAX
+# are ignored by the parser on platforms where they cannot be represented.
+for value in U+7FFFFFFF=1 U+7FFFFFFE-U+7FFFFFFF=2 \
+    U+FFFFFFFF=1 U+FFFFFFFE-U+FFFFFFFF=2; do
+	$TMUX set -g codepoint-widths "$value" || exit 1
+	[ "$($TMUX display-message -p alive)" = alive ] || exit 1
+done
+
+# Check that an ordinary range still includes both endpoints and stops there.
+$TMUX set -g codepoint-widths 'U+03B1-U+03B3=2' || exit 1
+$TMUX set -g @text 'αβγδ' || exit 1
+[ "$($TMUX display-message -p '#{w:@text}')" = 7 ] || exit 1
+$TMUX set -gu codepoint-widths || exit 1
+[ "$($TMUX display-message -p '#{w:@text}')" = 4 ] || exit 1
+
+$TMUX kill-server || exit 1
+SERVER=
+exit 0

regress/control-client-exit-stalled.sh

@@ -17,7 +17,7 @@ PATH=/bin:/usr/bin
 TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX="$TEST_TMUX -Ltest"
+TMUX="$TEST_TMUX -Ltest$$"
 $TMUX kill-server 2>/dev/null
 
 DIR=$(mktemp -d)

regress/control-client-exit.sh

@@ -19,7 +19,7 @@ PATH=/bin:/usr/bin
 TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX="$TEST_TMUX -Ltest"
+TMUX="$TEST_TMUX -Ltest$$"
 $TMUX kill-server 2>/dev/null
 
 DIR=$(mktemp -d)

regress/control-client-popup.sh

@@ -1,6 +1,7 @@
 #!/bin/sh
 
-# Popups require a tty overlay and cannot be displayed by a control client.
+# Popups require an attached terminal and cannot be displayed by a control
+# client.
 # A popup command from control mode must be ignored cleanly, leaving the
 # client command queue and server usable.
 

regress/control-client-run-shell-exit.sh

@@ -10,7 +10,7 @@ PATH=/bin:/usr/bin
 TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX="$TEST_TMUX -Ltest"
+TMUX="$TEST_TMUX -Ltest$$"
 $TMUX kill-server 2>/dev/null
 
 OUT=$(mktemp)

regress/control-client-sanity.sh

@@ -30,8 +30,11 @@ killw
 EOF
 sleep 1
 $TMUX has || exit 1
-$TMUX lsp -aF '#{pane_id} #{window_layout}' >$TMP || exit 1
-cat <<EOF|cmp -s $TMP - || exit 1
+# Use a control client to request legacy layouts, keeping only pane lines
+# from the control protocol output.
+$TMUX -C lsp -aF '#{pane_id} #{window_layout}' |
+	grep '^%[0-9]' >$TMP || exit 1
+cat <<EOF|cmp $TMP - || exit 1
 %0 f5ab,200x200,0,0[200x50,0,0,0,200x149,0,51,3]
 %3 f5ab,200x200,0,0[200x50,0,0,0,200x149,0,51,3]
 %2 dcbd,200x200,0,0[200x100,0,0,2,200x99,0,101,4]

regress/control-client-wait-exit.sh

@@ -10,7 +10,7 @@ PATH=/bin:/usr/bin
 TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX="$TEST_TMUX -Ltest"
+TMUX="$TEST_TMUX -Ltest$$"
 $TMUX kill-server 2>/dev/null
 
 FIFO=$(mktemp -u)

regress/copy-mode-source-blank.sh

@@ -0,0 +1,63 @@
+#!/bin/sh
+
+# Trimming a blank source must leave a visible line for cursor reflow.
+
+PATH=/bin:/usr/bin
+TERM=screen
+export PATH TERM
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$TMUX kill-server 2>/dev/null
+}
+trap cleanup 0
+trap 'exit 1' 1 2 3 15
+
+$TMUX new-session -d -x80 -y24 -s test 'sleep 100' || exit 1
+$TMUX set-option -g window-size manual || exit 1
+$TMUX new-window -t test:1 'sleep 100' || exit 1
+$TMUX resize-window -t test:0 -x20 -y24 || exit 1
+
+# Exercise widening, narrowing, and equal widths with no source history.
+for pair in '0 1' '1 0' '1 2'; do
+	set -- $pair
+	if [ "$2" = 2 ]; then
+		$TMUX new-window -t test:2 'sleep 100' || exit 1
+		$TMUX resize-window -t test:2 -x80 -y24 || exit 1
+	fi
+	source=test:$1.0
+	target=test:$2.0
+	[ "$($TMUX display-message -p -t "$source" '#{history_size}')" = 0 ] ||
+		fail "source has unexpected history"
+	$TMUX copy-mode -s "$source" -t "$target" || exit 1
+	$TMUX has-session -t test || fail "server died copying blank source"
+	[ "$($TMUX display-message -p -t "$target" \
+	    '#{pane_in_mode} #{copy_cursor_x} #{copy_cursor_y}')" = '1 0 0' ] ||
+		fail "blank source did not enter copy mode at the first cell"
+	$TMUX send-keys -t "$target" -X cancel || exit 1
+done
+
+# Real content still trims trailing empty lines, clamping the cursor to beta.
+$TMUX respawn-pane -k -t test:0.0 \
+	"printf 'alpha\r\nbeta\r\n\r\n\r\n'; exec sleep 100" || exit 1
+i=0
+while [ "$($TMUX display-message -p -t test:0.0 '#{cursor_y}')" != 4 ]; do
+	i=$((i + 1))
+	[ "$i" -lt 10 ] || fail "source output did not arrive"
+	sleep 1
+done
+$TMUX copy-mode -s test:0.0 -t test:1.0 || exit 1
+[ "$($TMUX display-message -p -t test:1.0 \
+    '#{pane_in_mode} #{copy_cursor_y} #{copy_cursor_line}')" = '1 1 beta' ] ||
+	fail "nonblank source content or trailing-line trimming changed"
+
+exit 0

regress/display-panes.sh

@@ -153,11 +153,13 @@ wait_format "$p0" '#{pane_in_mode}' '0'
 wait_option @picked "$p1"
 
 # Commands after display-panes run immediately while the mode remains.
+# Record the mode in the same command queue so client startup cannot race
+# the 500ms timeout.
 $TMUX set -g @after none || fail "set @after failed"
-$TMUX display-panes -Nd 500 -t "$p0" \; set -g @after fast ||
+$TMUX display-panes -Nd 500 -t "$p0" \; \
+    set -gF -t "$p0" @after '#{pane_mode}' ||
 	fail "display-panes immediate command failed"
-wait_option @after fast
-wait_format "$p0" '#{pane_mode}' 'panes-mode'
+wait_option @after 'panes-mode'
 wait_format "$p0" '#{pane_in_mode}' '0'
 
 # Existing zoom is restored on exit.

regress/floating-pane-border-style-cross-client.sh

@@ -0,0 +1,135 @@
+#!/bin/sh
+
+# Damage-only redraws must evaluate both active and inactive border styles
+# for each client, even though the cached border cells belong to the pane.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lborder-style-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lborder-style-outer-$$ -f/dev/null"
+CAPTURE=$DIR/capture
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_clients()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		count=$($INNER list-clients 2>/dev/null | wc -l)
+		[ "$count" -eq 2 ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "two inner clients did not attach"
+}
+
+wait_for_marker()
+{
+	target=$1
+	marker=$2
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t "$target" >"$CAPTURE" || exit 1
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "client in $target did not receive $marker"
+}
+
+cat >"$DIR/emitter.pl" <<'PERL'
+use strict;
+use warnings;
+
+$| = 1;
+for my $phase (1 .. 2) {
+	while (!-e "$ENV{TRIGGER}-$phase") {
+		select undef, undef, undef, 0.01;
+	}
+	# Change an unused palette entry and acknowledge it in the pane body.
+	print "\e]4;200;rgb:11/22/0$phase\a\e[1;1HDAMAGE$phase";
+}
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 60 -y 20 \
+    "TRIGGER='$DIR/trigger' perl '$DIR/emitter.pl'" || exit 1
+$INNER set -g status off || exit 1
+$INNER set -g window-size manual || exit 1
+$INNER set -g automatic-rename off || exit 1
+$INNER set -g status-interval 0 || exit 1
+$INNER set -g pane-border-lines simple || exit 1
+$INNER set -g pane-border-status top || exit 1
+$INNER set -g pane-border-format 'CLIENT=#{client_name}' || exit 1
+FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 35 -y 6 -X 5 -Y 5 \
+    'sleep 100') || exit 1
+
+$OUTER new-session -d -s outer -x 121 -y 20 'sleep 100' || exit 1
+$OUTER set -g status off || exit 1
+$OUTER set -g window-size manual || exit 1
+$OUTER set -g default-terminal screen || exit 1
+LEFT=$($OUTER display-message -p -t outer:0.0 '#{pane_id}') || exit 1
+RIGHT=$($OUTER split-window -h -PF '#{pane_id}' 'sleep 100') || exit 1
+for target in "$LEFT" "$RIGHT"; do
+	$OUTER respawn-pane -k -t "$target" "$INNER attach-session -t inner" ||
+	    exit 1
+done
+wait_for_clients
+
+NAME1=$($OUTER display-message -p -t "$LEFT" '#{pane_tty}') || exit 1
+NAME2=$($OUTER display-message -p -t "$RIGHT" '#{pane_tty}') || exit 1
+STYLE="fg=#{?#{==:#{client_name},$NAME1},red,blue}"
+$INNER set -g pane-border-style "$STYLE" || exit 1
+$INNER set -g pane-active-border-style "$STYLE" || exit 1
+
+# Capture just the floating pane's rows, excluding the acknowledgement in
+# the tiled pane. Exercise each cache by changing the floating pane's focus.
+phase=1
+while [ "$phase" -le 2 ]; do
+	if [ "$phase" -eq 2 ]; then
+		$INNER select-pane -t "$FLOAT" || exit 1
+	fi
+	$INNER refresh-client -t "$NAME1" || exit 1
+	$INNER refresh-client -t "$NAME2" || exit 1
+	sleep 0.5
+	for target in "$LEFT" "$RIGHT"; do
+		$OUTER capture-pane -pe -S 5 -E 10 -t "$target" \
+		    >"$DIR/before-$target" || exit 1
+	done
+	RED=$(printf '\033[31m')
+	BLUE=$(printf '\033[34m')
+	grep -Fq "$RED" "$DIR/before-$LEFT" || fail "missing red border"
+	grep -Fq "$BLUE" "$DIR/before-$RIGHT" || fail "missing blue border"
+
+	: >"$DIR/trigger-$phase"
+	wait_for_marker "$LEFT" "DAMAGE$phase"
+	wait_for_marker "$RIGHT" "DAMAGE$phase"
+	sleep 0.2
+	for target in "$LEFT" "$RIGHT"; do
+		$OUTER capture-pane -pe -S 5 -E 10 -t "$target" \
+		    >"$CAPTURE" || exit 1
+		diff -u "$DIR/before-$target" "$CAPTURE" ||
+		    fail "phase $phase changed $target's border style"
+	done
+	phase=$((phase + 1))
+done
+
+exit 0

regress/floating-pane-drag-ghost.sh

@@ -0,0 +1,108 @@
+#!/bin/sh
+
+# Regression test for a floating-pane drag bug: cmd_resize_pane_redraw_floating()
+# (cmd-resize-pane.c) reported damage for just a dragged floating pane's
+# content rectangle, not the one-cell border frame drawn around it (see the
+# "floating" case in screen-redraw.c, which draws that frame at
+# xoff-1/yoff-1 through xoff+sx/yoff+sy - one cell outside the pane's own
+# content area). Damage scoped to only the content area left the frame's
+# previous position undrawn as the pane moved, so dragging it left a trail
+# of un-erased border frames behind - visible as several "corners" stacked
+# up rather than just the pane's current one.
+#
+# This bug has nothing to do with images - it reproduces with a plain
+# floating pane and no image support required.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+TMUX2="$TEST_TMUX -LtestB$$ -f/dev/null"
+
+cleanup()
+{
+	$TMUX kill-server >/dev/null 2>&1
+	$TMUX2 kill-server >/dev/null 2>&1
+}
+fail()
+{
+	echo "$*" >&2
+	cleanup
+	exit 1
+}
+
+# drag STARTCOL STARTROW ENDCOL ENDROW
+#
+# Write a plain (unmodified) SGR button-1 press, drag update and release at
+# 1-based positions to the outer pane holding the inner client - this
+# matches the default MouseDown1Border/MouseDrag1Border bindings used to
+# move or resize a floating pane by its border.
+drag()
+{
+	scol="$1"
+	srow="$2"
+	ecol="$3"
+	erow="$4"
+
+	seq=$(printf '\033[<0;%s;%sM' "$scol" "$srow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 0.2
+	seq=$(printf '\033[<32;%s;%sM' "$ecol" "$erow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 0.2
+	seq=$(printf '\033[<0;%s;%sm' "$ecol" "$erow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 1
+}
+
+cleanup
+
+TMP=$(mktemp)
+trap "cleanup; rm -f $TMP" 0 1 15
+
+$TMUX new-session -d -s inner -x 60 -y 20 'sh -c "sleep 100"' || exit 1
+$TMUX set -g mouse on
+$TMUX set -g default-command 'sh -c "sleep 100"'
+
+FLOAT=$($TMUX new-pane -d -PF '#{pane_id}' -x 16 -y 5 -X 5 -Y 5) ||
+	fail "new-pane -X -Y failed"
+FTOP=$($TMUX display-message -p -t "$FLOAT" '#{pane_top}')
+FLEFT=$($TMUX display-message -p -t "$FLOAT" '#{pane_left}')
+FWIDTH=$($TMUX display-message -p -t "$FLOAT" '#{pane_width}')
+
+$TMUX2 new-session -d -x 60 -y 20 "$TMUX attach -t inner" || exit 1
+sleep 1
+OUTER=$($TMUX2 list-panes -F '#{pane_id}' | head -1)
+[ -n "$OUTER" ] || fail "No outer pane."
+
+# Sanity check: exactly one floating pane, so exactly one top-left corner,
+# before dragging anything.
+$TMUX2 capturep -p -t "$OUTER" >$TMP || fail "capture failed"
+n=$(grep -o '┌' $TMP | wc -l)
+[ "$n" -eq 1 ] || fail "sanity: expected 1 corner before drag, found $n"
+
+# Drag the floating pane by its top border (row FTOP-1, some column within
+# its width) down several rows in a few separate steps, then release. A
+# single drag() call already does press/motion/release, so call it several
+# times in a row to simulate a multi-step real drag.
+GRABCOL=$((FLEFT + FWIDTH / 2))
+STARTROW=$FTOP
+i=0
+while [ $i -lt 6 ]; do
+	newrow=$((STARTROW + i + 1))
+	drag $((GRABCOL + 1)) $((STARTROW + i)) $((GRABCOL + 1)) $newrow
+	i=$((i + 1))
+done
+
+$TMUX2 capturep -p -t "$OUTER" >$TMP || fail "capture failed"
+
+# Exactly one top-left corner should remain - the pane's current position.
+# This is expected to fail before the fix: multiple corners (a trail of
+# un-erased frames) would remain from the intermediate drag positions.
+n=$(grep -o '┌' $TMP | wc -l)
+[ "$n" -eq 1 ] || fail "expected exactly 1 corner after drag, found $n (ghost frames left behind)"
+
+exit 0

regress/floating-pane-drag-no-double-composite.sh

@@ -0,0 +1,88 @@
+#!/bin/sh
+
+# Each drag motion must draw the floating pane content once.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+cd "$DIR" || exit 1
+INNER="$TEST_TMUX -Ldoublecomp-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Ldoublecomp-outer-$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	cd /
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t outer:0.0 -l "$sequence" || exit 1
+	sleep 0.15
+}
+
+$INNER new-session -d -s inner -x 40 -y 15 "printf '\\033[15;1HOUTSIDE'; exec sleep 100" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+$INNER set-option -g status-interval 0 || exit 1
+$INNER set-option -g automatic-rename off || exit 1
+FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 15 -y 5 -X 5 -Y 2 \
+    "printf 'DRAGMARK'; exec sleep 100") || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 15 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Ldoublecomp-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+sleep 0.5
+
+XOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+YOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_top}')
+GRABCOL=$((XOFF + 3))
+BORDERROW=$YOFF
+
+# Begin capture after focus changes from the initial mouse press have settled.
+mouse 0 "$GRABCOL" "$BORDERROW" M
+$OUTER pipe-pane -O -t outer:0.0 "cat >'$DIR/output'" || exit 1
+$INNER refresh-client || exit 1
+sleep 0.5
+grep -aq DRAGMARK "$DIR/output" || fail "capture missed floating pane content"
+grep -aq OUTSIDE "$DIR/output" || fail "capture missed untouched row"
+offset=$(wc -c <"$DIR/output")
+
+i=0
+steps=6
+while [ "$i" -lt "$steps" ]; do
+	GRABCOL=$((GRABCOL + 1))
+	mouse 32 "$GRABCOL" "$BORDERROW" M
+	i=$((i + 1))
+done
+mouse 0 "$GRABCOL" "$BORDERROW" m
+sleep 0.3
+
+NEWXOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+[ "$NEWXOFF" -eq "$((XOFF + steps))" ] || fail "floating pane did not move six columns"
+tail -c +"$((offset + 1))" "$DIR/output" >"$DIR/drag-output"
+n=$(perl -0777 -ne '$n = () = /DRAGMARK/g; print "$n\n"' "$DIR/drag-output")
+[ "$n" -eq "$steps" ] ||
+	fail "$steps drag motions wrote the floating pane content $n times"
+
+exit 0

regress/floating-pane-drag-scrollbar-strip.sh

@@ -0,0 +1,159 @@
+#!/bin/sh
+
+# Regression test: dragging a floating pane across another pane's ordinary
+# content must not redraw that other pane's scrollbar, unless the drag
+# actually crosses the scrollbar's own strip.
+#
+# cmd_resize_pane_redraw_floating() (cmd-resize-pane.c) used to flag
+# PANE_REDRAWSCROLLBAR on any pane whose whole *body* intersected the
+# floating pane's old or new rectangle, rather than just its narrow
+# scrollbar strip - so dragging a floating pane back and forth over an
+# ordinary tiled pane's content (never touching its scrollbar) still
+# needlessly redrew that pane's scrollbar on every motion step. See
+# tmux-image-redraw-known-bugs.md for the full write-up.
+#
+# This is checked by giving the non-dragged pane a distinctive scrollbar
+# colour and counting how many times its SGR code appears in the client's
+# raw output while the floating pane is dragged vertically over that pane's
+# body, well clear of its scrollbar column: with the fix, it should never
+# reappear after the initial draw.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+TMUX2="$TEST_TMUX -LtestB$$ -f/dev/null"
+
+cleanup()
+{
+	$TMUX kill-server >/dev/null 2>&1
+	$TMUX2 kill-server >/dev/null 2>&1
+}
+fail()
+{
+	echo "$*" >&2
+	cleanup
+	exit 1
+}
+
+# drag STARTCOL STARTROW ENDCOL ENDROW
+drag()
+{
+	scol="$1"
+	srow="$2"
+	ecol="$3"
+	erow="$4"
+
+	seq=$(printf '\033[<0;%s;%sM' "$scol" "$srow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 0.2
+	seq=$(printf '\033[<32;%s;%sM' "$ecol" "$erow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 0.2
+	seq=$(printf '\033[<0;%s;%sm' "$ecol" "$erow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 0.5
+}
+
+cleanup
+
+TMP=$(mktemp)
+trap "cleanup; rm -f $TMP" 0 1 15
+
+$TMUX new-session -d -s inner -x 60 -y 20 'sh -c "sleep 100"' || exit 1
+$TMUX set -g mouse on || fail "set mouse failed"
+$TMUX set -g default-command 'sh -c "sleep 100"' || fail "set default-command failed"
+$TMUX set -g pane-scrollbars on || fail "set pane-scrollbars failed"
+
+$TMUX split-window -h -t inner 'sh -c "sleep 100"' || fail "split-window failed"
+
+PANES=$($TMUX list-panes -t inner -F '#{pane_id} #{pane_left}')
+LEFT=$(echo "$PANES" | sort -k2 -n | head -1 | cut -d' ' -f1)
+[ -n "$LEFT" ] || fail "could not identify left pane"
+
+# A distinctive scrollbar colour for the non-dragged (left) pane only.
+$TMUX set -p -t "$LEFT" pane-scrollbars-style 'fg=colour201,bg=colour17' ||
+	fail "set pane-scrollbars-style failed"
+
+ALEFT=$($TMUX display-message -p -t "$LEFT" '#{pane_left}')
+ATOP=$($TMUX display-message -p -t "$LEFT" '#{pane_top}')
+AWIDTH=$($TMUX display-message -p -t "$LEFT" '#{pane_width}')
+AHEIGHT=$($TMUX display-message -p -t "$LEFT" '#{pane_height}')
+[ "$AWIDTH" -gt 15 ] || fail "left pane too narrow for this test ($AWIDTH)"
+
+# A small floating pane placed well inside the left pane's content area,
+# clear of its (right-hand) scrollbar column by several columns.
+FLOAT=$($TMUX new-pane -d -PF '#{pane_id}' -x 8 -y 5 \
+    -X $((ALEFT + 2)) -Y $((ATOP + 2))) || fail "new-pane -X -Y failed"
+FTOP=$($TMUX display-message -p -t "$FLOAT" '#{pane_top}')
+FLEFT=$($TMUX display-message -p -t "$FLOAT" '#{pane_left}')
+FWIDTH=$($TMUX display-message -p -t "$FLOAT" '#{pane_width}')
+[ $((FLEFT + FWIDTH + 3)) -lt $((ALEFT + AWIDTH)) ] ||
+	fail "sanity: floating pane too close to the scrollbar column"
+
+# Start the outer session with a plain shell, then start capturing before
+# triggering the attach - starting the attach as the outer pane's initial
+# command would mean pipe-pane only starts after the attach-driven initial
+# redraw (which draws the scrollbars) has already happened, missing it.
+$TMUX2 new-session -d -x 60 -y 20 || exit 1
+OUTER=$($TMUX2 list-panes -F '#{pane_id}' | head -1)
+[ -n "$OUTER" ] || fail "No outer pane."
+$TMUX2 pipe-pane -t "$OUTER" -O "cat >$TMP" || fail "pipe-pane failed"
+$TMUX2 send-keys -t "$OUTER" -l "$TMUX attach -t inner" || fail "send attach failed"
+$TMUX2 send-keys -t "$OUTER" Enter || fail "send enter failed"
+sleep 1
+
+# Sanity check: the distinctive scrollbar colour reaches the client at all.
+grep -qa '48;5;201' $TMP || fail "sanity: scrollbar colour never reached the client"
+: >$TMP
+
+# Drag the floating pane straight up and down by its top border, staying at
+# a fixed column the whole time - this never crosses the left pane's
+# scrollbar strip, only its ordinary content.
+GRABCOL=$((FLEFT + FWIDTH / 2))
+row=$FTOP
+i=0
+while [ $i -lt 6 ]; do
+	newrow=$((row + 1))
+	drag $GRABCOL $row $GRABCOL $newrow
+	row=$newrow
+	i=$((i + 1))
+done
+i=0
+while [ $i -lt 6 ]; do
+	newrow=$((row - 1))
+	drag $GRABCOL $row $GRABCOL $newrow
+	row=$newrow
+	i=$((i + 1))
+done
+
+# The scrollbar colour should never reappear - its geometry never changed,
+# and the drag never crossed its column. This is expected to fail before
+# the fix - see the header comment.
+n=$(grep -ac '48;5;201' $TMP)
+[ "$n" -eq 0 ] ||
+	fail "left pane's scrollbar was redrawn $n times while dragging over its body only"
+
+# Cross the scrollbar and return, comparing each damaged redraw with a full
+# refresh to check that covering and uncovering its cells leaves no artifacts.
+offset=$((ALEFT + AWIDTH - FLEFT - FWIDTH / 2))
+for delta in "$offset" "$((-offset))"; do
+	oldleft=$($TMUX display-message -p -t "$FLOAT" '#{pane_left}')
+	newcol=$((GRABCOL + delta))
+	drag "$GRABCOL" "$row" "$newcol" "$row"
+	GRABCOL=$newcol
+	newleft=$($TMUX display-message -p -t "$FLOAT" '#{pane_left}')
+	[ "$newleft" -eq "$((oldleft + delta))" ] ||
+		fail "floating pane did not move across the scrollbar as expected"
+	before=$($TMUX2 capture-pane -pe -t "$OUTER" -S 0 -E "$((AHEIGHT - 1))")
+	$TMUX refresh-client || fail "refresh-client failed"
+	sleep 0.5
+	after=$($TMUX2 capture-pane -pe -t "$OUTER" -S 0 -E "$((AHEIGHT - 1))")
+	[ "$before" = "$after" ] ||
+		fail "scrollbar crossing differs from a full redraw"
+done
+
+exit 0

regress/floating-pane-drag-sync-no-self-defer.sh

@@ -0,0 +1,93 @@
+#!/bin/sh
+
+# Synchronized drag output must not cause a full redraw of untouched rows.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+cd "$DIR" || exit 1
+INNER="$TEST_TMUX -Lsyncdefer-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lsyncdefer-outer-$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	cd /
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t outer:0.0 -l "$sequence" || exit 1
+	sleep 0.15
+}
+
+$INNER new-session -d -s inner -x 40 -y 15 "printf '\\033[15;1HOUTSIDE'; exec sleep 100" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+$INNER set-option -g status-interval 0 || exit 1
+$INNER set-option -g automatic-rename off || exit 1
+FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 15 -y 5 -X 5 -Y 2 \
+    "printf 'DRAGMARK'; exec sleep 100") || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 15 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$INNER set-option -as terminal-features ',screen-256color:sync' || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lsyncdefer-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+sleep 0.5
+
+XOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+YOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_top}')
+GRABCOL=$((XOFF + 3))
+BORDERROW=$YOFF
+
+# Begin capture after focus changes from the initial mouse press have settled.
+mouse 0 "$GRABCOL" "$BORDERROW" M
+$OUTER pipe-pane -O -t outer:0.0 "cat >'$DIR/output'" || exit 1
+$INNER refresh-client || exit 1
+sleep 0.5
+grep -aq DRAGMARK "$DIR/output" || fail "capture missed floating pane content"
+grep -aq OUTSIDE "$DIR/output" || fail "capture missed untouched row"
+offset=$(wc -c <"$DIR/output")
+
+i=0
+steps=6
+while [ "$i" -lt "$steps" ]; do
+	GRABCOL=$((GRABCOL + 1))
+	mouse 32 "$GRABCOL" "$BORDERROW" M
+	i=$((i + 1))
+done
+mouse 0 "$GRABCOL" "$BORDERROW" m
+sleep 0.3
+
+NEWXOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+[ "$NEWXOFF" -eq "$((XOFF + steps))" ] || fail "floating pane did not move six columns"
+tail -c +"$((offset + 1))" "$DIR/output" >"$DIR/drag-output"
+n=$(perl -0777 -ne '$n = () = /DRAGMARK/g; print "$n\n"' "$DIR/drag-output")
+[ "$n" -ge "$steps" ] || fail "drag output did not reach the client"
+perl -0777 -ne 'exit(/\e\[\?2026h/ ? 0 : 1)' "$DIR/drag-output" ||
+    fail "drag did not use synchronized output"
+if grep -aq OUTSIDE "$DIR/drag-output"; then
+	fail "synchronized drag redrew an untouched row"
+fi
+
+exit 0

regress/floating-pane-drag-wide-character-right.sh

@@ -0,0 +1,206 @@
+#!/bin/sh
+
+# Mirror of floating-pane-drag-wide-character.sh for the *right* edge of a
+# damage rectangle. redraw_damage_grow_span_clip() (screen-redraw.c) widens
+# a damage rectangle's right edge by one cell whenever it isn't already at
+# the span's own edge, to pull in a wide character's base half when the
+# edge lands on its padding half - but it did this unconditionally, with no
+# check of which half it was actually touching. When the edge instead
+# already lands cleanly on a fresh character's base cell (a character fully
+# outside the range), growing right pulls in just that base cell -
+# tty_draw_line() sees it can't fit that character's full width in the
+# remaining range (tty_draw_line_get_empty()'s gc->data.width > nx check)
+# and clears it, exactly as the left-edge bug cleared a neighbouring
+# character's padding half.
+#
+# As with the left-edge test, the exact column parity needs to be
+# deterministic to actually catch it. This constructs it by creating the
+# floating pane, checking its real position, and recreating it one column
+# over if necessary until the vacated rectangle's right edge lands on a
+# base cell.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lwidecharr-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lwidecharr-outer-$$ -f/dev/null"
+EMITTER=$DIR/emitter.pl
+BASE=$DIR/base
+CAPTURE=$DIR/capture
+FLOAT=
+PANEWIDTH=12
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+slice_columns()
+{
+	# Extract terminal columns [COL1, COL2) from lines [ROW1, ROW2] of
+	# $1, decoding UTF-8 - the pane's own new position (well clear of
+	# this range) must not affect the comparison, so this only looks at
+	# the narrow strip actually vacated, not the whole line. capture-pane
+	# text has one decoded character per double-width cell pair (every
+	# character here is width 2), so terminal columns are converted to
+	# character indices by halving before slicing.
+	perl -CSD -e '
+		my ($row1, $row2, $col1, $col2, $file) = @ARGV;
+		open my $fh, "<:encoding(UTF-8)", $file or die $!;
+		my @lines = <$fh>;
+		my $c1 = int($col1 / 2);
+		my $c2 = int(($col2 + 1) / 2);
+		for my $n ($row1 .. $row2) {
+			my $line = $lines[$n - 1];
+			$line =~ s/\R\z//;
+			print substr($line, $c1, $c2 - $c1), "\n";
+		}
+	' "$ROW1" "$ROW2" "$COL1" "$COL2" "$1"
+}
+
+wait_old_rows_restored()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		slice_columns "$BASE" >"$DIR/want"
+		slice_columns "$CAPTURE" >"$DIR/got"
+		cmp -s "$DIR/want" "$DIR/got" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "wide characters under the floating pane's vacated right edge were not restored"
+}
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t outer:0.0 -l "$sequence" || exit 1
+	sleep 0.1
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+binmode STDOUT, ':encoding(UTF-8)';
+$| = 1;
+for my $row (1 .. 10) {
+	print "\e[$row;1H", chr(0x754c) x 20;
+}
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 40 -y 10 "perl '$EMITTER'" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+$INNER set-option -g pane-scrollbars off || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 10 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lwidecharr-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_client
+wait_outer_has '界界界'
+$OUTER capture-pane -p -t outer:0.0 >"$BASE" || exit 1
+
+# Create the floating pane, then check its actual resulting position. Try
+# adjacent starting columns until the vacated rectangle's right edge
+# (xoff + PANEWIDTH + 1, the border-grown exclusive end - see
+# window_pane_damage_floating(), window.c) lands on an even (base-cell)
+# column.
+startx=5
+tries=0
+while [ "$tries" -lt 2 ]; do
+	[ -n "$FLOAT" ] && $INNER kill-pane -t "$FLOAT" 2>/dev/null
+	FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x "$PANEWIDTH" -y 3 \
+	    -X "$startx" -Y 5 \
+	    'sh -c "printf FLOATMARK; exec sleep 100"') || exit 1
+	sleep 0.2
+	XOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+	YOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_top}')
+	oldright=$((XOFF + PANEWIDTH + 1))
+	if [ $((oldright % 2)) -eq 0 ]; then
+		break
+	fi
+	startx=$((startx + 1))
+	tries=$((tries + 1))
+done
+[ $(((XOFF + PANEWIDTH + 1) % 2)) -eq 0 ] ||
+	fail "could not find bad-parity starting column"
+
+wait_outer_has FLOATMARK
+
+ROW1=$((YOFF + 1))
+ROW2=$((YOFF + 3))
+COL1=$((XOFF + PANEWIDTH - 2))
+COL2=$((XOFF + PANEWIDTH + 2))
+
+# Grab the pane's top border a couple of columns in (avoiding the corner
+# cells) and drag it well clear of its old rectangle - far enough right
+# that its new position starts past the checked columns above (which sit
+# just past the pane's *original* right edge).
+GRABCOL=$((XOFF + 3))
+BORDERROW=$((YOFF))
+
+seq=$(printf '\033[<0;%s;%sM' "$GRABCOL" "$BORDERROW")
+$OUTER send-keys -t outer:0.0 -l "$seq" || exit 1
+sleep 0.1
+seq=$(printf '\033[<32;%s;%sM' "$((GRABCOL + 20))" "$BORDERROW")
+$OUTER send-keys -t outer:0.0 -l "$seq" || exit 1
+sleep 0.1
+seq=$(printf '\033[<0;%s;%sm' "$((GRABCOL + 20))" "$BORDERROW")
+$OUTER send-keys -t outer:0.0 -l "$seq" || exit 1
+sleep 0.1
+
+NEWXOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+[ "$NEWXOFF" != "$XOFF" ] || fail "sanity: floating pane did not move (still at $XOFF)"
+
+wait_old_rows_restored
+
+exit 0

regress/floating-pane-drag-wide-character.sh

@@ -0,0 +1,200 @@
+#!/bin/sh
+
+# Damage at a floating pane's vacated edge must always redraw a complete
+# grid character. redraw_damage_grow_span_clip() (screen-redraw.c) widens a
+# damage rectangle's left edge by one cell whenever it isn't already at the
+# span's own edge, to pull in a wide character's base half when the edge
+# lands on its padding half - but it did this unconditionally, with no
+# check of which half it was actually touching. When the edge instead
+# already lands cleanly on a fresh character's base cell, growing left
+# walks into the *previous*, unrelated character's padding cell and blanks
+# it (tty_draw_line() treats any leading padding cell as proof its own
+# range starts mid-character).
+#
+# This is a general damage-composition bug, not specific to any one kind of
+# pane, but the exact column parity needs to be deterministic to actually
+# catch it (a lucky parity draws fine). This constructs it by creating the
+# floating pane, checking its real position (the border-framing offset
+# added to -X is not something to hand-compute), and recreating it one
+# column over if necessary until the vacated rectangle's left edge lands on
+# a base cell.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lwidechar-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lwidechar-outer-$$ -f/dev/null"
+EMITTER=$DIR/emitter.pl
+BASE=$DIR/base
+CAPTURE=$DIR/capture
+FLOAT=
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+slice_columns()
+{
+	# Extract terminal columns [COL1, COL2) from lines [ROW1, ROW2] of
+	# $1, decoding UTF-8 - the pane's own new position (well clear of
+	# this range) must not affect the comparison, so this only looks at
+	# the narrow strip actually vacated, not the whole line. capture-pane
+	# text has one decoded character per double-width cell pair (every
+	# character here is width 2), so terminal columns are converted to
+	# character indices by halving before slicing.
+	perl -CSD -e '
+		my ($row1, $row2, $col1, $col2, $file) = @ARGV;
+		open my $fh, "<:encoding(UTF-8)", $file or die $!;
+		my @lines = <$fh>;
+		my $c1 = int($col1 / 2);
+		my $c2 = int(($col2 + 1) / 2);
+		for my $n ($row1 .. $row2) {
+			my $line = $lines[$n - 1];
+			$line =~ s/\R\z//;
+			print substr($line, $c1, $c2 - $c1), "\n";
+		}
+	' "$ROW1" "$ROW2" "$COL1" "$COL2" "$1"
+}
+
+wait_old_rows_restored()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		slice_columns "$BASE" >"$DIR/want"
+		slice_columns "$CAPTURE" >"$DIR/got"
+		cmp -s "$DIR/want" "$DIR/got" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "wide characters under the floating pane's vacated edge were not restored"
+}
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t outer:0.0 -l "$sequence" || exit 1
+	sleep 0.1
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+binmode STDOUT, ':encoding(UTF-8)';
+$| = 1;
+for my $row (1 .. 10) {
+	print "\e[$row;1H", chr(0x754c) x 20;
+}
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 40 -y 10 "perl '$EMITTER'" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+$INNER set-option -g pane-scrollbars off || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 10 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lwidechar-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_client
+wait_outer_has '界界界'
+$OUTER capture-pane -p -t outer:0.0 >"$BASE" || exit 1
+
+# Create the floating pane, then check its actual resulting position. Try
+# adjacent starting columns until the vacated rectangle's left edge
+# (xoff - 1) lands on an even (base-cell) column - the odd case is the one
+# every earlier manual test happened to land on by chance.
+startx=5
+tries=0
+while [ "$tries" -lt 2 ]; do
+	[ -n "$FLOAT" ] && $INNER kill-pane -t "$FLOAT" 2>/dev/null
+	FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 12 -y 3 -X "$startx" \
+	    -Y 5 'sh -c "printf FLOATMARK; exec sleep 100"') || exit 1
+	sleep 0.2
+	XOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+	YOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_top}')
+	oldleft=$((XOFF - 1))
+	if [ $((oldleft % 2)) -eq 0 ]; then
+		break
+	fi
+	startx=$((startx + 1))
+	tries=$((tries + 1))
+done
+[ $(((XOFF - 1) % 2)) -eq 0 ] || fail "could not find bad-parity starting column"
+
+wait_outer_has FLOATMARK
+
+ROW1=$((YOFF + 1))
+ROW2=$((YOFF + 3))
+COL1=$((XOFF - 4))
+COL2=$((XOFF + 4))
+
+# Grab the pane's top border a couple of columns in (avoiding the corner
+# cells) and drag it well clear of its old rectangle.
+GRABCOL=$((XOFF + 3))
+BORDERROW=$((YOFF))
+
+seq=$(printf '\033[<0;%s;%sM' "$GRABCOL" "$BORDERROW")
+$OUTER send-keys -t outer:0.0 -l "$seq" || exit 1
+sleep 0.1
+seq=$(printf '\033[<32;%s;%sM' "$((GRABCOL + 15))" "$BORDERROW")
+$OUTER send-keys -t outer:0.0 -l "$seq" || exit 1
+sleep 0.1
+seq=$(printf '\033[<0;%s;%sm' "$((GRABCOL + 15))" "$BORDERROW")
+$OUTER send-keys -t outer:0.0 -l "$seq" || exit 1
+sleep 0.1
+
+NEWXOFF=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+[ "$NEWXOFF" != "$XOFF" ] || fail "sanity: floating pane did not move (still at $XOFF)"
+
+wait_old_rows_restored
+
+exit 0

regress/floating-pane-geometry.sh

@@ -268,5 +268,149 @@ $TMUX kill-pane -t "$floating" || exit 1
 $TMUX kill-pane -t "$right" || exit 1
 $TMUX kill-pane -t "$lower" || exit 1
 
+# --- Floating panes clamped when the window shrinks (issue #5581, PR #5582) ---
+#
+# layout_resize clamps floating panes back inside the window when it shrinks:
+# move them and, only if they cannot fit, shrink them (never below
+# PANE_MINIMUM). A floating cell is the pane's content, so with the default
+# single-line border the clamp counts 1 cell of border per side, exactly as
+# layout_floating_args_parse does on creation; with no border it counts 0.
+# Each case below gets its own window, since resize-window fixes a window at
+# a manual size for the rest of its life.
+
+# Case 1: a lone floating pane -- break-pane -W on a window's only pane --
+# takes the early-return path in layout_resize, added during PR #5582's
+# review round, since there is no tiled tree to walk.
+win=$($TMUX new-window -dPF '#{window_id}') ||
+	fail "new-window for lone float failed"
+
+# -x 20 -y 6 -> pane 18x4; -X 60 -Y 18 -> pane_left 61, pane_top 19: with the
+# border, the footprint is columns 60-79, rows 18-23, flush with the 80x24
+# window's right and bottom edges, so the float fits before it is shrunk.
+$TMUX break-pane -W -s "$win" -x 20 -y 6 -X 60 -Y 18 ||
+	fail "break-pane -W for lone float failed"
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_width}')"  18
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_height}')" 4
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_left}')"   61
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_top}')"    19
+
+# Shrink to 40x16. The float still fits at its own size (18 <= 40-2, 4 <=
+# 16-2) so only its position moves, flush to the new right/bottom edges:
+# xoff = 40 - 18 - 1 = 21; yoff = 16 - 4 - 1 = 11.
+$TMUX resize-window -t "$win" -x 40 -y 16 ||
+	fail "resize-window (lone float) failed"
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_width}')"  18
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_height}')" 4
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_left}')"   21
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_top}')"    11
+
+# Case 5: grow the window back. The clamp must not chase the window back
+# outward -- it only ever pulls a float in, never restores where it was.
+$TMUX resize-window -t "$win" -x 80 -y 24 ||
+	fail "resize-window grow (lone float) failed"
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_width}')"  18
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_height}')" 4
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_left}')"   21
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_top}')"    11
+$TMUX kill-window -t "$win" || exit 1
+
+# Case 2: the same float, but with a tiled sibling surviving alongside it, so
+# the window's root cell stays tiled and layout_resize takes the normal path
+# (the clamp call after layout_fix_offsets) instead of the early return
+# above. Same geometry as case 1, so the same numbers should come out.
+win=$($TMUX new-window -dPF '#{window_id}') ||
+	fail "new-window for tiled sibling failed"
+$TMUX split-window -t "$win" 'sleep 100' ||
+	fail "split-window for tiled sibling failed"
+$TMUX break-pane -W -s "$win" -x 20 -y 6 -X 60 -Y 18 ||
+	fail "break-pane -W for tiled sibling failed"
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_width}')"  18
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_height}')" 4
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_left}')"   61
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_top}')"    19
+
+$TMUX resize-window -t "$win" -x 40 -y 16 ||
+	fail "resize-window (tiled sibling) failed"
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_width}')"  18
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_height}')" 4
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_left}')"   21
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_top}')"    11
+$TMUX kill-window -t "$win" || exit 1
+
+# Case 3: new-pane float, the original repro from issue #5581 and the PR
+# body -- also the normal path, via the tiled base pane new-window creates.
+win=$($TMUX new-window -dPF '#{window_id}') ||
+	fail "new-window for new-pane repro failed"
+$TMUX resize-window -t "$win" -x 120 -y 40 ||
+	fail "resize-window to 120x40 failed"
+
+# -x 30 -y 10 -> pane 28x8; -X 85 -Y 25 -> pane_left 86, pane_top 26.
+floating=$($TMUX new-pane -t "$win" -dPF '#{pane_id}' \
+	-x 30 -y 10 -X 85 -Y 25 'sleep 100') ||
+	fail "new-pane for new-pane repro failed"
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_width}')"  28
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_height}')" 8
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_left}')"   86
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_top}')"    26
+
+# Shrink to 60x20: xoff = 60 - 28 - 1 = 31; yoff = 20 - 8 - 1 = 11.
+$TMUX resize-window -t "$win" -x 60 -y 20 ||
+	fail "resize-window (new-pane repro) failed"
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_width}')"  28
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_height}')" 8
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_left}')"   31
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_top}')"    11
+$TMUX kill-window -t "$win" || exit 1
+
+# Case 4: a float that already fits inside the shrunk window is left alone --
+# assert position and size are both unchanged, not just one of them.
+win=$($TMUX new-window -dPF '#{window_id}') ||
+	fail "new-window for untouched float failed"
+
+# -x 20 -y 6 -> pane 18x4; -X 8 -Y 3 -> pane_left 9, pane_top 4 (as at the top
+# of this file). Footprint columns 8-27, rows 3-8: well inside 60x20 too.
+floating=$($TMUX new-pane -t "$win" -dPF '#{pane_id}' \
+	-x 20 -y 6 -X 8 -Y 3 'sleep 100') ||
+	fail "new-pane for untouched float failed"
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_width}')"  18
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_height}')" 4
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_left}')"   9
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_top}')"    4
+
+$TMUX resize-window -t "$win" -x 60 -y 20 ||
+	fail "resize-window (untouched float) failed"
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_width}')"  18
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_height}')" 4
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_left}')"   9
+must_equal "$($TMUX display-message -p -t "$floating" '#{pane_top}')"    4
+$TMUX kill-window -t "$win" || exit 1
+
+# Case 6: pad = 0, via the pane-border-lines window option set to none. The
+# border arithmetic differs here (no -2/+1 adjustment either on creation or
+# in the clamp).
+win=$($TMUX new-window -dPF '#{window_id}') ||
+	fail "new-window for pad=0 float failed"
+$TMUX set-option -w -t "$win" pane-border-lines none ||
+	fail "set pane-border-lines none failed"
+
+# No border: -x 20 -y 6 -> pane 20x6 directly; -X 60 -Y 18 -> pane_left 60,
+# pane_top 18 directly. Footprint (== content, no border) is columns 60-79,
+# rows 18-23: flush right/bottom of the 80x24 window, same as case 1.
+$TMUX break-pane -W -s "$win" -x 20 -y 6 -X 60 -Y 18 ||
+	fail "break-pane -W for pad=0 float failed"
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_width}')"  20
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_height}')" 6
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_left}')"   60
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_top}')"    18
+
+# Shrink to 40x16 with pad=0: xoff = 40 - 20 - 0 = 20; yoff = 16 - 6 - 0 = 10.
+$TMUX resize-window -t "$win" -x 40 -y 16 ||
+	fail "resize-window (pad=0 float) failed"
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_width}')"  20
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_height}')" 6
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_left}')"   20
+must_equal "$($TMUX display-message -p -t "$win" '#{pane_top}')"    10
+$TMUX kill-window -t "$win" || exit 1
+
 $TMUX kill-server 2>/dev/null
 exit 0

regress/floating-pane-offscreen-alternate-redraw.sh

@@ -0,0 +1,102 @@
+#!/bin/sh
+
+# Returning from the alternate screen must redraw the visible part of a
+# floating pane clipped at the left edge, the top edge, or both.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Loffscreen-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Loffscreen-outer-$$ -f/dev/null"
+EMITTER=$DIR/emitter.pl
+CAPTURE=$DIR/capture
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+$| = 1;
+for my $row (1 .. 5) {
+	print "\e[$row;1H", 'A' x 15;
+}
+while (!-e "$ENV{TRIGGER}-alternate") {
+	select undef, undef, undef, 0.01;
+}
+print "\e[?1049h";
+for my $row (1 .. 5) {
+	print "\e[$row;1H", 'B' x 15;
+}
+while (!-e "$ENV{TRIGGER}-restore") {
+	select undef, undef, undef, 0.01;
+}
+print "\e[?1049l";
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 40 -y 10 'sleep 100' || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 10 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Loffscreen-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+for position in left top both; do
+	case "$position" in
+	left) x=-5; y=2 ;;
+	top) x=5; y=-2 ;;
+	both) x=-5; y=-2 ;;
+	esac
+	FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 15 -y 5 -X "$x" -Y "$y" \
+	    "TRIGGER='$DIR/$position' perl '$EMITTER'") || exit 1
+	[ "$($INNER display-message -p -t "$FLOAT" '#{pane_left},#{pane_top}')" = "$((x + 1)),$((y + 1))" ] ||
+	    fail "$position: floating pane has unexpected position"
+	wait_outer_has AAAAA
+	cp "$CAPTURE" "$DIR/primary"
+	: >"$DIR/$position-alternate"
+	wait_outer_has BBBBB
+	: >"$DIR/$position-restore"
+	wait_outer_has AAAAA
+	cmp -s "$DIR/primary" "$CAPTURE" ||
+	    fail "$position: primary screen was not completely restored"
+	$INNER kill-pane -t "$FLOAT" || exit 1
+done
+
+exit 0

regress/floating-pane-prompt-wide-character.sh

@@ -0,0 +1,179 @@
+#!/bin/sh
+
+# A damage rectangle's clip range is grown to avoid splitting a wide
+# character, but redraw_damage_grow_span_clip() (screen-redraw.c) only ever
+# checks the span's own pane *content* grid (wp->screen) for that. For a
+# REDRAW_SPAN_PANE span, that same range is then also handed to
+# redraw_damage_draw_pane_prompt() to recompose the pane's separately
+# rendered prompt (wp->prompt, e.g. from "command-prompt -P") over the
+# damaged sub-range - but the prompt is drawn into its own, freshly
+# allocated one-line screen, unrelated to the pane's content grid, so a
+# range grown (or left ungrown) against the content is not necessarily
+# grown correctly for the prompt's own wide characters.
+#
+# This is invisible when the pane's own content is plain ASCII (as here):
+# redraw_damage_grow_span_clip() never finds anything to grow against, so
+# the raw, ungrown geometric range is passed straight through to the
+# prompt - and if that range's edge lands mid-character in the *prompt's*
+# grid, tty_draw_line() clears the character it cuts through
+# (tty_draw_line_get_empty()'s gc->data.width > nx check, for a trailing
+# base cell with no room left for its padding half).
+#
+# The trigger is a palette change (OSC 4) in a tiled pane that is one half
+# of a vertical split running the full height of the window - occluded
+# under the floating pane, but still geometrically triggering a redraw of
+# its own rectangle. Positioned so the split boundary falls inside the
+# floating pane's own CJK prompt, this reproduces exactly Codex's report:
+# "a floating pane containing a CJK prompt across a tiled-pane boundary -
+# a palette update in the tiled pane blanks a prompt character."
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+cd "$DIR" || exit 1
+INNER="$TEST_TMUX -Lpromptwide-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lpromptwide-outer-$$ -f/dev/null"
+EMITTER=$DIR/emitter.pl
+CAPTURE=$DIR/capture
+FLOAT=
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	cd /
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+wait_prompt_row_intact()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		line=$(sed -n "${PROMPTROW}p" "$CAPTURE")
+		case $line in
+		*"$PROMPTTEXT"*) return 0 ;;
+		esac
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "the CJK prompt was not intact after the palette-triggered damage - got: $line"
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+$| = 1;
+my $line = <STDIN>;
+print "\e]4;1;rgb:11/22/33\e\\";
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 60 -y 12 "perl '$EMITTER'" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+LEFT=$($INNER list-panes -t inner -F '#{pane_id}') || exit 1
+
+# Split so the boundary between the two tiled panes falls at column 17 -
+# used below to pick a floating-pane column that lands the boundary
+# mid-character inside the prompt.
+RIGHT=$($INNER split-window -t inner -h -l 43 -PF '#{pane_id}' \
+    'sleep 100') || exit 1
+RX=$($INNER display-message -p -t "$RIGHT" '#{pane_left}') || exit 1
+
+# Create the floating pane, then check its actual resulting position (the
+# border-framing offset added to -X is not something to hand-compute). Try
+# adjacent starting columns until the split boundary lands on an odd
+# (padding-half) column of the prompt's own numbering, and within the
+# prompt's 12-column width.
+startx=10
+tries=0
+while [ "$tries" -lt 4 ]; do
+	[ -n "$FLOAT" ] && $INNER kill-pane -t "$FLOAT" 2>/dev/null
+	FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 24 -y 5 -X "$startx" \
+	    -Y 2 "sh -c 'i=0; while [ \$i -lt 10 ]; do \
+printf AAAAAAAAAAAAAAAAAAAAAA\\\\n; i=\$((i+1)); done; sleep 100'") ||
+	    exit 1
+	sleep 0.2
+	X1=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+	Y1=$($INNER display-message -p -t "$FLOAT" '#{pane_top}')
+	H1=$($INNER display-message -p -t "$FLOAT" '#{pane_height}')
+	local=$((RX - X1 - 1))
+	if [ "$local" -ge 1 ] && [ "$local" -le 11 ] &&
+	    [ $((local % 2)) -eq 1 ]; then
+		break
+	fi
+	startx=$((startx + 1))
+	tries=$((tries + 1))
+done
+local=$((RX - X1 - 1))
+[ "$local" -ge 1 ] && [ "$local" -le 11 ] && [ $((local % 2)) -eq 1 ] ||
+	fail "could not find bad-parity starting column"
+
+$OUTER new-session -d -s outer -x 60 -y 12 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lpromptwide-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_client
+wait_outer_has AAAAAAAAAAAAAAAAAAAAAA
+CLIENT=$($INNER list-clients -F '#{client_name}') || exit 1
+
+$INNER select-pane -t "$FLOAT" || exit 1
+PROMPTTEXT=$(printf '\344\270\255' | perl -CSD -ne 'print $_ x 6')
+$INNER command-prompt -b -P -t "$CLIENT" -p "$PROMPTTEXT" \
+    'display-message -- %1' || exit 1
+wait_outer_has "$PROMPTTEXT"
+
+PROMPTROW=$((Y1 + H1))
+
+# Trigger the damage: unblock the emitter so it fires the palette change in
+# the left tiled pane, which is occluded under (but geometrically overlaps)
+# the floating pane's prompt row.
+$INNER send-keys -t "$LEFT" Enter || exit 1
+
+wait_prompt_row_intact
+
+exit 0

regress/floating-pane-status-cross-client.sh

@@ -0,0 +1,151 @@
+#!/bin/sh
+
+# Damage redraws must show each client's own pane status, even though the
+# cached status screen is shared between clients.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lstatuscc-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lstatuscc-outer-$$ -f/dev/null"
+CAPTURE=$DIR/capture
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_clients()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		count=$($INNER list-clients 2>/dev/null | wc -l)
+		[ "$count" -eq 2 ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "two inner clients did not attach"
+}
+
+wait_for_marker()
+{
+	target=$1
+	marker=$2
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t "$target" >"$CAPTURE" || exit 1
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "client in $target did not receive $marker"
+}
+
+cat >"$DIR/emitter.pl" <<'PERL'
+use strict;
+use warnings;
+
+$| = 1;
+for my $phase (1 .. 4) {
+	while (!-e "$ENV{TRIGGER}-$phase") {
+		select undef, undef, undef, 0.01;
+	}
+	# Change an unused palette entry and acknowledge it in the pane body.
+	print "\e]4;200;rgb:11/22/0$phase\a\e[1;1HDAMAGE$phase";
+}
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 60 -y 20 \
+    "TRIGGER='$DIR/trigger' perl '$DIR/emitter.pl'" || exit 1
+$INNER set -g status off || exit 1
+$INNER set -g window-size manual || exit 1
+$INNER set -g automatic-rename off || exit 1
+$INNER set -g status-interval 0 || exit 1
+$INNER set -g pane-border-lines simple || exit 1
+$INNER set -g pane-border-status top || exit 1
+$INNER set -g pane-border-format 'CLIENT=<#{client_name}>' || exit 1
+FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 35 -y 6 -X 5 -Y 5 \
+    'sleep 100') || exit 1
+
+$OUTER new-session -d -s outer -x 121 -y 20 'sleep 100' || exit 1
+$OUTER set -g status off || exit 1
+$OUTER set -g window-size manual || exit 1
+$OUTER set -g default-terminal screen || exit 1
+LEFT=$($OUTER display-message -p -t outer:0.0 '#{pane_id}') || exit 1
+RIGHT=$($OUTER split-window -h -PF '#{pane_id}' 'sleep 100') || exit 1
+for target in "$LEFT" "$RIGHT"; do
+	$OUTER respawn-pane -k -t "$target" "$INNER attach-session -t inner" ||
+	    exit 1
+done
+wait_for_clients
+
+NAME1=$($OUTER display-message -p -t "$LEFT" '#{pane_tty}') || exit 1
+NAME2=$($OUTER display-message -p -t "$RIGHT" '#{pane_tty}') || exit 1
+
+# Disable periodic status updates above and trigger damage without a command
+# that also requests a status redraw. Each client must keep its own title.
+$INNER refresh-client -t "$NAME1" || exit 1
+$INNER refresh-client -t "$NAME2" || exit 1
+sleep 0.5
+for phase in 0 1 2; do
+	if [ "$phase" -ne 0 ]; then
+		: >"$DIR/trigger-$phase"
+		wait_for_marker "$LEFT" "DAMAGE$phase"
+		wait_for_marker "$RIGHT" "DAMAGE$phase"
+		sleep 0.2
+	fi
+	for target in "$LEFT" "$RIGHT"; do
+		if [ "$target" = "$LEFT" ]; then
+			name=$NAME1
+			other=$NAME2
+		else
+			name=$NAME2
+			other=$NAME1
+		fi
+		$OUTER capture-pane -p -S 5 -E 10 -t "$target" \
+		    >"$CAPTURE" || exit 1
+		grep -Fq "CLIENT=<$name>" "$CAPTURE" ||
+		    fail "phase $phase: missing $name's pane status"
+		if grep -Fq "CLIENT=<$other>" "$CAPTURE"; then
+			fail "phase $phase: $name received $other's pane status"
+		fi
+	done
+done
+
+# Leave just one client so a cache keyed only by client would remain stale.
+$OUTER respawn-pane -k -t "$RIGHT" 'sleep 100' || exit 1
+i=0
+while [ "$($INNER list-clients | wc -l)" -ne 1 ]; do
+	[ "$i" -lt 50 ] || fail "second client did not detach"
+	sleep 0.1
+	i=$((i + 1))
+done
+$INNER set-environment -g TEST_STATUS_VALUE initial || exit 1
+$INNER set -g pane-border-format 'VALUE=#{TEST_STATUS_VALUE}' || exit 1
+$INNER refresh-client -t "$NAME1" || exit 1
+wait_for_marker "$LEFT" VALUE=initial
+for phase in 3 4; do
+	# Changing the environment does not itself request a status redraw.
+	$INNER set-environment -g TEST_STATUS_VALUE "phase$phase" || exit 1
+	: >"$DIR/trigger-$phase"
+	wait_for_marker "$LEFT" "DAMAGE$phase"
+	wait_for_marker "$LEFT" "VALUE=phase$phase"
+done
+
+exit 0

regress/floating-pane-status-format.sh

@@ -0,0 +1,102 @@
+#!/bin/sh
+
+# Resizing a floating pane must refresh session status formats which depend on
+# its geometry, not only the pane scene and borders.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lfloating-status-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lfloating-status-outer-$$ -f/dev/null"
+CAPTURE=$DIR/capture
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+wait_outer_has_status()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		tail -1 "$CAPTURE" | grep -q "$marker" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client status did not show $marker"
+}
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t outer:0.0 -l "$sequence" || exit 1
+	sleep 0.1
+}
+
+$INNER new-session -d -s inner -x 50 -y 12 'sleep 100' || exit 1
+FLOAT=$($INNER new-pane -PF '#{pane_id}' -x 10 -y 5 -X 5 -Y 3 \
+    'sleep 100') || fail "could not create floating pane"
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+$INNER set-option -g status on || exit 1
+$INNER set-option -g status-position bottom || exit 1
+$INNER set-option -g status-left 'WIDTH=#{pane_width}' || exit 1
+$INNER set-option -g status-right '' || exit 1
+$INNER set-option -g status-interval 0 || exit 1
+
+$OUTER new-session -d -s outer -x 50 -y 12 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lfloating-status-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_client
+OLD_WIDTH=$($INNER display-message -p -t "$FLOAT" '#{pane_width}')
+wait_outer_has_status "WIDTH=$OLD_WIDTH"
+
+RIGHT=$($INNER display-message -p -t "$FLOAT" '#{pane_right}')
+TOP=$($INNER display-message -p -t "$FLOAT" '#{pane_top}')
+X=$((RIGHT + 2))
+Y=$((TOP + 2))
+
+# Grab the right frame and enlarge the floating pane.
+mouse 0 "$X" "$Y" M
+mouse 32 "$((X + 1))" "$Y" M
+mouse 32 "$((X + 8))" "$Y" M
+mouse 0 "$((X + 8))" "$Y" m
+
+NEW_WIDTH=$($INNER display-message -p -t "$FLOAT" '#{pane_width}')
+[ "$NEW_WIDTH" -ne "$OLD_WIDTH" ] || fail "floating pane was not resized"
+wait_outer_has_status "WIDTH=$NEW_WIDTH"
+
+exit 0

regress/floating-pane-zoom.sh

@@ -0,0 +1,158 @@
+#!/bin/sh
+
+# Moving, resizing and reordering an over-zoom float must leave the tiled
+# pane zoomed, and the changes must survive an explicit unzoom.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+trap '$TMUX kill-server 2>/dev/null' 0
+trap 'exit 1' 1 2 15
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+run()
+{
+	$TMUX "$@" || fail "failed: $*"
+}
+
+check()
+{
+	got=$(run display-message -p -t "$1" "$2") || exit 1
+	[ "$got" = "$3" ] || fail "$1 $2: got '$got', expected '$3'"
+}
+
+check_zoom()
+{
+	check "$base" '#{window_zoomed_flag}:#{pane_zoomed_flag}' '1:1'
+	check "$float" '#{pane_floating_flag}:#{pane_active}' "1:$active"
+	check "$base" '#{@unzoomed}' ''
+}
+
+run new-session -d -x 80 -y 24
+base=$(run display-message -p '#{pane_id}') || exit 1
+other=$(run split-window -dPF '#{pane_id}') || exit 1
+layout=$(run display-message -p '#{window_layout}') || exit 1
+run set-hook -g window-unzoomed 'set -g @unzoomed 1'
+
+# Cover creation before and after zoom, with both the float and the tiled
+# pane active. Modal panes use the same over-zoom flag.
+for mode in before after detached modal; do
+	if [ "$mode" != before ]; then
+		run resize-pane -Z -t "$base"
+	fi
+	case "$mode" in
+	detached) flags=-Ad; active=0 ;;
+	modal) flags=-O; active=1 ;;
+	*) flags=-A; active=1 ;;
+	esac
+	float=$(run new-pane "$flags" -PF '#{pane_id}' -t "$base" \
+	    -x 20 -y 8 -X 8 -Y 3 '') || exit 1
+	if [ "$mode" = before ]; then
+		run resize-pane -Z -t "$base"
+	fi
+	run set -gu @unzoomed
+	check_zoom
+
+	run move-pane -t "$float" -D
+	check "$float" '#{pane_top}' 5
+	check_zoom
+	run move-pane -t "$float" -U 2 -R 3 -L 1
+	check "$float" '#{pane_left}:#{pane_top}' '11:3'
+	check_zoom
+	run move-pane -t "$float" -X 25% -Y 25%
+	check "$float" '#{pane_left}:#{pane_top}' '21:7'
+	check_zoom
+	run move-pane -t "$float" -P bottom-right
+	check "$float" '#{pane_left}:#{pane_top}' '61:17'
+	check_zoom
+	run resize-pane -t "$float" -x 30 -y 10
+	check "$float" '#{pane_width}:#{pane_height}' '28:8'
+	check_zoom
+	run resize-pane -t "$float" -U 1 -L 2
+	check "$float" '#{pane_left}:#{pane_top}:#{pane_width}:#{pane_height}' \
+	    '59:16:30:9'
+	check_zoom
+	run move-pane -t "$float" -P centre
+	check "$float" '#{pane_left}:#{pane_top}' '25:7'
+	check_zoom
+
+	# Failed commands must not change zoom either.
+	for command in 'move-pane -D invalid' 'move-pane -P invalid' \
+	    'move-pane -z invalid' 'resize-pane -x invalid' \
+	    'resize-pane -D invalid'; do
+		$TMUX $command -t "$float" 2>/dev/null &&
+		    fail "unexpected success: $command"
+		check_zoom
+	done
+
+	run resize-pane -Z -t "$base"
+	check "$float" '#{pane_left}:#{pane_top}:#{pane_width}:#{pane_height}' \
+	    '25:7:30:9'
+	run kill-pane -t "$float"
+	check "$base" '#{window_layout}' "$layout"
+done
+
+# Put an ordinary (hidden while zoomed) float between two over-zoom floats
+# in the stacking order. Reordering must skip it when counting visible
+# positions, but keep all floats ahead of the tiled panes after unzoom.
+back=$(run new-pane -AdPF '#{pane_id}' -t "$base" '') || exit 1
+hidden=$(run new-pane -dPF '#{pane_id}' -t "$base" '') || exit 1
+float=$(run new-pane -AdPF '#{pane_id}' -t "$base" '') || exit 1
+active=0
+run resize-pane -Z -t "$base"
+run set -gu @unzoomed
+
+for position in backward back forward-loop; do
+	run move-pane -t "$float" -P front
+	run move-pane -t "$float" -P "$position"
+	check "$float" '#{pane_z}' 1
+	check "$back" '#{pane_z}' 0
+	check_zoom
+done
+for position in forward front backward-loop; do
+	run move-pane -t "$float" -P back
+	run move-pane -t "$float" -P "$position"
+	check "$float" '#{pane_z}' 0
+	check "$back" '#{pane_z}' 1
+	check_zoom
+done
+for z in 1 0 99; do
+	run move-pane -t "$float" -z "$z"
+	want=$z
+	[ "$z" = 99 ] && want=1
+	check "$float" '#{pane_z}' "$want"
+	check_zoom
+done
+run resize-pane -Z -t "$base"
+check "$float" '#{pane_z}' 2
+check "$base" '#{pane_z}' 4
+run kill-pane -t "$hidden"
+run kill-pane -t "$back"
+
+# Explicit zoom toggling and operations on tiled panes retain their
+# existing behaviour. The over-zoom flag alone does not make a pane a float:
+# zooming the float itself gives it a tiled cell until unzoom.
+run resize-pane -Z -t "$float"
+check "$float" '#{pane_zoomed_flag}:#{pane_floating_flag}' '1:0'
+run resize-pane -t "$float" -x 25
+check "$float" '#{window_zoomed_flag}:#{pane_floating_flag}:#{pane_width}' \
+    '0:1:23'
+run resize-pane -Z -t "$base"
+run resize-pane -t "$other" -D 1
+check "$base" '#{window_zoomed_flag}' 0
+
+# A hidden ordinary float must still be unzoomed before resizing it.
+hidden=$(run new-pane -dPF '#{pane_id}' -t "$base" '') || exit 1
+run resize-pane -Z -t "$base"
+run resize-pane -t "$hidden" -x 25
+check "$hidden" '#{window_zoomed_flag}:#{pane_floating_flag}:#{pane_width}' \
+    '0:1:23'
+
+exit 0

regress/format-fuzzy.sh

@@ -7,6 +7,8 @@ TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
 TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+trap '$TMUX kill-server 2>/dev/null' 0
+trap 'exit 1' 1 2 15
 
 # test_format $format $expected_result
 test_format()

regress/format-modifiers.sh

@@ -18,6 +18,24 @@ export TZ LANG LC_ALL
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
 TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+FIFO1="${TMPDIR:-/tmp}/fmt-l-$$-1"
+FIFO2="${TMPDIR:-/tmp}/fmt-l-$$-2"
+HOLD1=
+HOLD2=
+CC1=
+CC2=
+
+cleanup()
+{
+	for pid in $HOLD1 $HOLD2 $CC1 $CC2; do
+		kill "$pid" 2>/dev/null
+		wait "$pid" 2>/dev/null
+	done
+	$TMUX kill-server 2>/dev/null
+	rm -f "$FIFO1" "$FIFO2"
+}
+trap cleanup 0
+trap 'exit 1' 1 2 15
 
 ESC=$(printf '\033')
 
@@ -579,8 +597,6 @@ assert_alive "verbose loop expansion"
 
 # L loops over attached clients.  Attach two control-mode clients, each held
 # open by a background process keeping a FIFO's write end open.
-FIFO1="${TMPDIR:-/tmp}/fmt-l-$$-1"
-FIFO2="${TMPDIR:-/tmp}/fmt-l-$$-2"
 rm -f "$FIFO1" "$FIFO2"
 mkfifo "$FIFO1" "$FIFO2" || exit 1
 # Hold the write ends open so the control clients stay attached.
@@ -605,9 +621,9 @@ test_format "#{L/nr:x}" "xx"
 test_format "#{L/r:x}" "xx"
 # Now detach one and confirm the count drops to one.
 kill $HOLD2 2>/dev/null
+wait $HOLD2 2>/dev/null
+HOLD2=
 sleep 1
 test_format "#{L:x}" "x"
-kill $HOLD1 $CC1 $CC2 2>/dev/null
-rm -f "$FIFO1" "$FIFO2"
 
 exit 0

regress/format-strings.sh

@@ -7,6 +7,8 @@ TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
 TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+trap '$TMUX kill-server 2>/dev/null' 0
+trap 'exit 1' 1 2 15
 
 # test_format $format $expected_result
 test_format()

regress/hooks-lifecycle.sh

@@ -76,14 +76,14 @@ $TMUX set-hook -g session-closed \
 	fail "set-hook session-closed failed"
 
 # The only pane of the only window of a session exits: pane-exited, then
-# window-unlinked, then session-closed, each seeing the dead object in the
+# session-closed, then window-unlinked, each seeing the dead object in the
 # hook formats.
 pane=$($TMUX new -d -s doomed -n dwin -P -F '#{pane_id}' 'true') ||
 	fail "new-session doomed failed"
 wait_for @log \
-	"|pane-exited:$pane|window-unlinked:doomed:dwin|session-closed:doomed"
+	"|pane-exited:$pane|session-closed:doomed|window-unlinked:doomed:dwin"
 assert_unchanged @log \
-	"|pane-exited:$pane|window-unlinked:doomed:dwin|session-closed:doomed"
+	"|pane-exited:$pane|session-closed:doomed|window-unlinked:doomed:dwin"
 
 # The dead pane, window and session cannot be used as targets but the
 # server survives.
@@ -110,14 +110,14 @@ $TMUX set-hook -g pane-exited \
 	'set -gF @log "#{@log}|pane-exited:#{hook_pane}"' ||
 	fail "restore pane-exited hook failed"
 
-# kill-window on the last window: window-unlinked then session-closed but
+# kill-window on the last window: session-closed then window-unlinked but
 # no pane-exited for the panes in the killed window.
 $TMUX set -g @log '' || fail "reset @log failed"
 $TMUX new -d -s doomed2 -n dwin2 || fail "new-session doomed2 failed"
 $TMUX splitw -d -t doomed2:0 || fail "split-window doomed2 failed"
 $TMUX kill-window -t doomed2:0 || fail "kill-window failed"
-wait_for @log '|window-unlinked:doomed2:dwin2|session-closed:doomed2'
-assert_unchanged @log '|window-unlinked:doomed2:dwin2|session-closed:doomed2'
+wait_for @log '|session-closed:doomed2|window-unlinked:doomed2:dwin2'
+assert_unchanged @log '|session-closed:doomed2|window-unlinked:doomed2:dwin2'
 $TMUX has -t main || fail "server died after kill-window chain"
 
 # kill-session: session-closed fires first, then window-unlinked for its

regress/if-shell-error.sh

@@ -12,7 +12,8 @@ $TMUX kill-server 2>/dev/null
 
 TMP=$(mktemp)
 OUT=$(mktemp)
-trap "rm -f $TMP $OUT" 0 1 15
+trap 'rm -f "$TMP" "$OUT"; $TMUX kill-server 2>/dev/null' 0
+trap 'exit 1' 1 2 15
 
 cat <<EOF >$TMP
 if 'true' 'wibble wobble'

regress/input-common.inc

@@ -4,6 +4,9 @@ TERM=screen
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
 TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
 
+# Keep panes alive until the next case or cleanup, without reading replies.
+INPUT_HOLD='while :; do sleep 3600; done'
+
 TMP=$(mktemp)
 EXP=$(mktemp)
 trap 'rm -f "$TMP" "$EXP"; $TMUX kill-server 2>/dev/null' 0 1 15
@@ -37,10 +40,10 @@ start_pane_hlimit()
 
 	$TMUX kill-server 2>/dev/null
 	sleep 0.1
-	$TMUX new-session -d -x 1 -y 1 -s test-setup "sleep 2" || exit 1
+	$TMUX new-session -d -x 1 -y 1 -s test-setup "$INPUT_HOLD" || exit 1
 	$TMUX set-option -g history-limit "$hlimit" || exit 1
 	$TMUX new-session -d -x "$sx" -y "$sy" -s "$name" \
-	    "printf '$seq'; sleep 2" || exit 1
+	    "printf '$seq'; $INPUT_HOLD" || exit 1
 	$TMUX kill-session -t test-setup
 	sleep 0.3
 }

regress/input-keys.sh

@@ -22,7 +22,19 @@ assert_key () {
 	      clear-history -t$W \; \
 	      send-keys -t$W "$key" 'EOL' || exit 1
 
-	actual_code=$($TMUX capturep -pt$W | \
+	# cat echoes the keys back asynchronously, so wait for the EOL marker
+	# to reach the pane instead of capturing straight away.
+	i=0
+	while [ $i -lt 50 ]; do
+		screen=$($TMUX capturep -pt$W)
+		case "$screen" in
+		*EOL*) break ;;
+		esac
+		i=$((i + 1))
+		sleep 0.1
+	done
+
+	actual_code=$(printf '%s\n' "$screen" | \
 			      head -1 | \
 			      sed -e 's/EOL.*$//')
 

regress/input-malformed.sh

@@ -2,6 +2,38 @@
 
 . ./input-common.inc
 
+# Wait for the terminator and following text to reach the parser.
+check_discard()
+{
+	name=$1
+	printf 'OK\n' >"$EXP"
+	i=0
+	while [ "$i" -lt 300 ]; do
+		capture_grid "$name" >"$TMP"
+		cmp -s "$TMP" "$EXP" && return 0
+		sleep 0.05
+		i=$((i + 1))
+	done
+	fail "$name (timed out waiting for discard)"
+}
+
+# The missing-terminator timer may expire before the string limit is reached
+# on a slow build. Clear any payload printed after the timeout, then check
+# that the string did not change the title and normal output has resumed.
+test_discard()
+{
+	name=$1
+	prefix=$2
+	start_cmd "$name" 8 3 "$INPUT_HOLD"
+	$TMUX select-pane -T discard-test || exit 1
+	$TMUX respawn-pane -k \
+	    "perl -e 'print qq{$prefix}, q{x} x 1100000, qq{\e\\\\\e[H\e[2JOK}'; $INPUT_HOLD" || exit 1
+	check_discard "$name"
+	$TMUX display-message -p -t "$name:" '#{pane_title}' >"$TMP" || exit 1
+	printf 'discard-test\n' >"$EXP"
+	cmp "$TMP" "$EXP" || fail "$name title"
+}
+
 start_cmd csi-param-discard 8 3 \
     "perl -e 'print qq{\e[}, q{1} x 80, qq{\030OK}'; sleep 2"
 check_capture csi-param-discard 'OK'
@@ -10,13 +42,8 @@ start_cmd csi-interm-discard 8 3 \
     "perl -e 'print qq{\e[    \030OK}'; sleep 2"
 check_capture csi-interm-discard 'OK'
 
-start_cmd osc-discard 8 3 \
-    "perl -e 'print qq{\e]2;}, q{x} x 1100000, qq{\e\\\\OK}'; sleep 2"
-check_capture osc-discard 'OK'
-
-start_cmd apc-discard 8 3 \
-    "perl -e 'print qq{\e_}, q{x} x 1100000, qq{\e\\\\OK}'; sleep 2"
-check_capture apc-discard 'OK'
+test_discard osc-discard '\e]2;'
+test_discard apc-discard '\e_'
 
 start_pane unknown-csi 8 3 '\033[?9999zOK'
 check_capture unknown-csi 'OK'

regress/input-scroll.sh

@@ -51,7 +51,7 @@ $TMUX kill-server 2>/dev/null
 sleep 0.1
 $TMUX new-session -d -x 5 -y 3 -s history \; \
     set-option -g history-limit 3 \; \
-    respawn-pane -k "printf '01\n02\n03\n04\n05\n06'; sleep 2" || exit 1
+    respawn-pane -k "printf '01\n02\n03\n04\n05\n06'; $INPUT_HOLD" || exit 1
 sleep 0.3
 $TMUX capture-pane -pN -t history: -S - -E - | normalize_capture >"$TMP"
 printf "%s\n" '01

regress/kill-session-zoomed.sh

@@ -0,0 +1,28 @@
+#!/bin/sh
+
+# Killing a session whose window is zoomed must not crash the server:
+# window_destroy used to unzoom the window, which resized the panes and
+# fired pane-resized with the window in the payload, and releasing that
+# reference destroyed the window a second time.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+$TMUX kill-server 2>/dev/null
+
+$TMUX -f/dev/null new -d -sfoo || exit 1
+$TMUX split-window -d -h -tfoo:0 || exit 1
+$TMUX resize-pane -Z -tfoo:0 || exit 1
+$TMUX new -d -sbar || exit 1
+$TMUX kill-session -tfoo || exit 1
+$TMUX has-session -tbar || exit 1
+
+# The same with the zoomed window in a session killed by kill-server.
+$TMUX new -d -sbaz || exit 1
+$TMUX split-window -d -v -tbaz:0 || exit 1
+$TMUX resize-pane -Z -tbaz:0 || exit 1
+$TMUX kill-server || exit 1
+
+exit 0

regress/layout-custom.sh

@@ -50,7 +50,8 @@
 #   layout it names is a single cell or a split;
 # - a window whose only tiled pane has been killed, which leaves it with a
 #   floating cell as its layout root or with a root node holding nothing but
-#   floating cells, producing no v1 dump at all, and being parsed as v1;
+#   floating cells, producing an empty v1 body with a checksum, and being
+#   parsed as v1;
 # - the %layout-change notification, in both formats at once: two control
 #   clients watching one layout change, only one of which has asked for new
 #   layouts, and the number of notifications a change produces in each format;
@@ -376,10 +377,7 @@ must_equal 'Layout after select-pane back' "$(layout L:two)" "$SPLIT"
 
 # With nothing zoomed the two layout formats agree.
 #
-# The zoomed case is deliberately not covered here. While a pane is zoomed
-# #{window_layout} dumps the saved (unzoomed) layout and
-# #{window_visible_layout} the zoomed one, but that depends on how zooming
-# stashes the layout root rather than on anything in layout-custom.c.
+# Zoomed layouts are checked below with floating panes.
 must_equal 'Visible layout' "$(visible_layout L:two)" "$SPLIT"
 
 # ---------------------------------------------------------------------------
@@ -703,6 +701,42 @@ must_contain 'Floating layout back z-index' "$floating" '"z":1'
 check_ok select-layout -t L:float "$floating"
 must_equal 'Floating layout after round trip' "$(raw_layout L:float)" "$floating"
 
+# A dump taken while zoomed must retain the unzoomed floating z-indexes.
+# Check hidden floats, floats above zoom, and a mixture of the two.
+for flags in '' A mixed; do
+	check_ok new-window -d -t L: -n zoom
+	zt=$($TMUX display-message -p -t L:zoom '#{pane_id}')
+	check_ok split-window -d -h -t "$zt"
+	case "$flags" in
+	A|mixed) first=-Ad ;;
+	*) first=-d ;;
+	esac
+	case "$flags" in
+	A) second=-Ad ;;
+	*) second=-d ;;
+	esac
+	check_ok new-pane "$first" -t "$zt" -x 20 -y 6 ''
+	check_ok new-pane "$second" -t "$zt" -x 30 -y 8 ''
+	for pane in 0 2 3; do
+		check_ok select-pane -t "L:zoom.$pane"
+		before=$(raw_layout L:zoom)
+		legacy=$(v1_layout L:zoom)
+		check_ok resize-pane -Z -t "L:zoom.$pane"
+		during=$(raw_layout L:zoom)
+		must_equal 'Layout while zoomed' "$during" "$before"
+		must_equal 'Legacy layout while zoomed' \
+		    "$(v1_layout L:zoom)" "$legacy"
+		must_equal 'Zoom after dumping layout' \
+		    "$($TMUX display-message -p -t L:zoom '#{window_zoomed_flag}')" 1
+		must_differ 'Visible layout while zoomed' \
+		    "$(visible_layout L:zoom)" "$(layout L:zoom)"
+		check_ok select-layout -t L:zoom "$during"
+		must_equal 'Round trip from zoomed layout' \
+		    "$(raw_layout L:zoom)" "$before"
+	done
+	check_ok kill-window -t L:zoom
+done
+
 # ---------------------------------------------------------------------------
 # Floating panes and the legacy (v1) format.
 #
@@ -838,12 +872,12 @@ must_equal 'Panes left with one floating pane' \
 	"$($TMUX display-message -p -t L:gone1 '#{window_panes}')" '1'
 
 # The floating cell is the root and there is nothing tiled under it, so there is
-# no v1 dump to make. In particular the floating cell must not be written out on
+# only an empty v1 body to dump. The floating cell must not be written out on
 # its own, which would be a layout claiming the window is the size and position
 # of the floating pane with no pane in it at all.
 got=$(v1_layout L:gone1)
 check_ok display-message -p alive
-must_equal 'v1 dump with one floating pane and no tiled panes' "$got" ''
+must_equal 'v1 dump with one floating pane and no tiled panes' "$got" '0000,'
 
 # Two floating panes left, so the node keeps two children, does not collapse,
 # and stays the root with nothing but floating cells in it.
@@ -856,11 +890,11 @@ must_equal 'Panes left with two floating panes' \
 	"$($TMUX display-message -p -t L:gone2 '#{window_panes}')" '2'
 
 # The node is the root this time rather than the floating cell, but it has no
-# tiled cell anywhere under it either, so there is still no v1 dump to make -
+# tiled cell anywhere under it either, so the v1 body is still empty -
 # and making one must not take the server with it.
 got=$(v1_layout L:gone2)
 check_ok display-message -p alive
-must_equal 'v1 dump with two floating panes and no tiled panes' "$got" ''
+must_equal 'v1 dump with two floating panes and no tiled panes' "$got" '0000,'
 
 # Nor must parsing a v1 layout against it. There is no tiled pane for the
 # layout to name, so whether it is applied or rejected is the format's business;

regress/modal-pane.sh

@@ -337,9 +337,9 @@ $TMUX set -g @modal-prefix no
 $TMUX set -g @modal-root no
 $TMUX bind -n z set -g @modal-root yes
 
-modal=$($TMUX new-pane -OKPF '#{pane_id}' -t "$p0" \
+modal=$($TMUX new-pane -ODKPF '#{pane_id}' -t "$p0" \
     -x 20 -y 5 -X 20 -Y 10 'cat') ||
-	fail "new-pane -OK failed"
+	fail "new-pane -ODK failed"
 sleep 1
 $TMUX2 send-keys -t "$OUTER" C-b x z Enter
 sleep 1
@@ -356,9 +356,151 @@ new_left=$(fmt "$modal" '#{pane_left}')
 new_top=$(fmt "$modal" '#{pane_top}')
 [ "$new_left" -gt "$left" ] || [ "$new_top" -gt "$top" ] ||
 	fail "key-capturing modal pane did not move"
+$TMUX2 send-keys -t "$OUTER" Escape
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+modal=$($TMUX new-pane -ODKPF '#{pane_id}' -t "$p0" \
+    -x 20 -y 5 -X 20 -Y 10 'trap "" INT; exec cat') ||
+	fail "new-pane -ODK failed"
+sleep 1
+$TMUX2 send-keys -t "$OUTER" C-c
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+# A dead modal does not close on Escape or C-c without -D.
+modal=$($TMUX new-pane -OPF '#{pane_id}' -t "$p0" \
+    -x 20 -y 5 -X 20 -Y 10 'sleep 1') ||
+	fail "new-pane -O failed"
+check_ok set-option -p -t "$modal" remain-on-exit on
+sleep 2
+must_equal "$(fmt "$modal" '#{pane_dead}:#{pane_modal_flag}')" 1:1
+$TMUX2 send-keys -t "$OUTER" Escape
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" "$modal"
 check_ok kill-pane -t "$modal"
 sleep 1
 
+# failed-key closes successful panes and retains failed panes until a key.
+modal=$($TMUX new-pane -OPF '#{pane_id}' -t "$p0" \
+    -x 20 -y 5 -X 20 -Y 10 'sleep 1') ||
+	fail "new-pane -O failed"
+check_ok set-option -p -t "$modal" remain-on-exit failed-key
+sleep 2
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+modal=$($TMUX new-pane -OPF '#{pane_id}' -t "$p0" \
+    -x 20 -y 5 -X 20 -Y 10 'sleep 1; exit 1') ||
+	fail "new-pane -O failed"
+check_ok set-option -p -t "$modal" remain-on-exit failed-key
+sleep 2
+must_equal "$(fmt "$modal" '#{pane_dead}:#{pane_modal_flag}')" 1:1
+must_equal "$($TMUX show-options -pv -t "$modal" remain-on-exit)" failed-key
+$TMUX2 send-keys -t "$OUTER" a
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+$TMUX bind P display-popup -E -t "$p0" -w 20 -h 5 -T popup-title 'cat'
+$TMUX2 send-keys -t "$OUTER" C-b P
+sleep 1
+modal=$(fmt modal:0 '#{window_modal_pane}')
+[ -n "$modal" ] || fail "display-popup did not create a modal pane"
+must_equal "$(fmt "$modal" '#{pane_title}')" popup-title
+must_equal "$($TMUX show-options -pv -t "$modal" pane-border-status)" top
+must_equal "$($TMUX show-options -pv -t "$modal" pane-border-format)" \
+	'#{pane_title}'
+$TMUX2 send-keys -t "$OUTER" C-b x z Enter
+sleep 1
+must_equal "$($TMUX show -gv @modal-prefix)" no
+must_equal "$($TMUX show -gv @modal-root)" no
+case "$($TMUX capture-pane -pt "$modal")" in
+*xz*) ;;
+*) fail "keys did not reach display-popup pane" ;;
+esac
+$TMUX2 send-keys -t "$OUTER" Escape
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" "$modal"
+$TMUX2 send-keys -t "$OUTER" C-c
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+# Creating a popup pane must not fire the split-window hook.
+check_ok set-hook -t modal after-split-window \
+	"set-option -g @popup-after-split yes"
+check_ok set-option -g @popup-after-split no
+check_ok display-popup -E -t "$p0" true
+must_equal "$($TMUX show-option -gv @popup-after-split)" no
+check_ok set-hook -u -t modal after-split-window
+
+# A borderless popup must not create a zero-sized pane in a tiny window.
+check_ok new-window -d -t modal: -n popup-small 'cat'
+check_ok set-option -w -t modal:popup-small window-size manual
+check_ok resize-window -t modal:popup-small -x 1 -y 1
+small=$(fmt modal:popup-small '#{pane_id}')
+check_ok bind Z display-popup -B -t "$small" 'cat'
+$TMUX2 send-keys -t "$OUTER" C-b Z
+sleep 1
+must_equal "$(fmt modal:popup-small '#{window_panes}')" 1
+must_equal "$(fmt modal:popup-small '#{window_modal_pane}')" ''
+
+$TMUX bind D display-popup -t "$p0" -w 20 -h 5 'printf done'
+$TMUX2 send-keys -t "$OUTER" C-b D
+sleep 2
+modal=$(fmt modal:0 '#{window_modal_pane}')
+[ -n "$modal" ] || fail "retained display-popup was not created"
+must_equal "$(fmt "$modal" '#{pane_dead}')" 1
+case "$($TMUX capture-pane -pt "$modal")" in
+*'Pane is dead'*) fail "display-popup showed remain-on-exit message" ;;
+esac
+$TMUX2 send-keys -t "$OUTER" a
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" "$modal"
+$TMUX2 send-keys -t "$OUTER" Escape
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+$TMUX bind K display-popup -k -t "$p0" -w 20 -h 5 'printf done'
+$TMUX2 send-keys -t "$OUTER" C-b K
+sleep 2
+modal=$(fmt modal:0 '#{window_modal_pane}')
+[ -n "$modal" ] || fail "display-popup -k was not created"
+must_equal "$(fmt "$modal" '#{pane_dead}')" 1
+$TMUX2 send-keys -t "$OUTER" a
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+$TMUX bind F display-popup -EE -t "$p0" -w 20 -h 5 'exit 1'
+$TMUX2 send-keys -t "$OUTER" C-b F
+sleep 2
+modal=$(fmt modal:0 '#{window_modal_pane}')
+[ -n "$modal" ] || fail "failed display-popup -EE did not remain"
+must_equal "$(fmt "$modal" '#{pane_dead}')" 1
+$TMUX2 send-keys -t "$OUTER" a
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" "$modal"
+$TMUX2 send-keys -t "$OUTER" Escape
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" "$modal"
+check_ok kill-pane -t "$modal"
+sleep 1
+
+check_ok display-popup -EE -t "$p0" true
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+$TMUX bind G display-popup -EE -k -t "$p0" -w 20 -h 5 'exit 1'
+$TMUX2 send-keys -t "$OUTER" C-b G
+sleep 2
+modal=$(fmt modal:0 '#{window_modal_pane}')
+[ -n "$modal" ] || fail "failed display-popup -EE -k did not remain"
+must_equal "$(fmt "$modal" '#{pane_dead}')" 1
+must_equal "$($TMUX show-options -pv -t "$modal" remain-on-exit)" failed-key
+$TMUX2 send-keys -t "$OUTER" a
+sleep 1
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
+check_ok display-popup -EE -k -t "$p0" true
+must_equal "$(fmt modal:0 '#{window_modal_pane}')" ''
+
 # A nonmodal floating pane may remain above zoom, and switching between it and
 # the zoomed tiled pane must not unzoom the window.
 check_ok new-window -d -t modal: -n float-over-zoom 'cat'

regress/mode-tree-menu-position.sh

@@ -0,0 +1,71 @@
+#!/bin/sh
+
+# Chooser menus are centred on the mouse using their displayed width. A
+# hidden title must not move a borderless menu away from the mouse.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+TMUX2="$TEST_TMUX -LtestB$$ -f/dev/null"
+
+cleanup()
+{
+	$TMUX kill-server >/dev/null 2>&1
+	$TMUX2 kill-server >/dev/null 2>&1
+}
+trap cleanup 0 1 15
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+$TMUX new-session -d -s short -x 100 -y 30 'sleep 100' || exit 1
+$TMUX set -g mouse on || exit 1
+$TMUX set -g status off || exit 1
+$TMUX2 new-session -d -x 100 -y 30 "$TMUX attach" || exit 1
+sleep 1
+
+for name in short aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa; do
+	$TMUX rename-session "$name" || exit 1
+	for lines in none single padded; do
+		$TMUX set -g menu-border-lines "$lines" || exit 1
+		$TMUX choose-tree -s || exit 1
+		sleep 1
+
+		# Right-button press at window (60, 0), away from either edge.
+		seq=$(printf '\033[<2;61;1M')
+		$TMUX2 send-keys -l "$seq" || exit 1
+		sleep 1
+
+		row=2
+		column=54
+		if [ "$lines" = none ]; then
+			row=1
+		elif [ "$name" != short ]; then
+			column=31
+		fi
+		text=$($TMUX2 capture-pane -p | awk -v row="$row" \
+		    -v column="$column" 'NR == row {
+			# Keep byte offsets equal to columns with non-Unicode awk.
+			gsub(/│/, "|")
+			print substr($0, column, 7)
+		    }')
+		[ "$text" = 'Select ' ] || \
+		    fail "$lines menu for $name: expected Select at ($column, $row), got '$text'"
+
+		# Close the menu, release the button, then leave the chooser.
+		$TMUX2 send-keys Escape || exit 1
+		seq=$(printf '\033[<2;61;1m')
+		$TMUX2 send-keys -l "$seq" || exit 1
+		$TMUX2 send-keys q || exit 1
+		sleep 1
+	done
+done
+
+exit 0

regress/options-values.sh

@@ -86,6 +86,11 @@ check_value "-gv status-keys" "vi"
 check_fail "unknown value: bogus" set -g status-keys bogus
 check_value "-gv status-keys" "vi"
 
+# pane-border-lines accepts rounded as a pane border style.
+check_ok set -gw pane-border-lines rounded
+check_value "-gwv pane-border-lines" "rounded"
+check_ok set -gw pane-border-lines single
+
 # --- flag options ---------------------------------------------------------
 #
 # focus-events is an on/off flag.  Setting with no value toggles it; explicit

regress/pane-ops.sh

@@ -104,6 +104,25 @@ assert_alive()
 	fi
 }
 
+# Compare layout geometry and pane ordering, ignoring the active pane and
+# last-pane history in the JSON layout. Selection is checked separately.
+pane_layout()
+{
+	$TMUX display-message -p -t "$1" '#{window_layout}' |
+		sed 's/,"a":true//g; s/,"l":[0-9][0-9]*//g'
+}
+
+check_layout()
+{
+	out=$(pane_layout "$1")
+	if [ "$out" != "$2" ]; then
+		echo "Layout for '$1' wrong."
+		echo "Expected: '$2'"
+		echo "But got:  '$out'"
+		exit 1
+	fi
+}
+
 # ---------------------------------------------------------------------------
 # split-window geometry.
 
@@ -309,12 +328,12 @@ check_ok kill-pane -t "$p6"
 
 # Zoom and unzoom preserve the exact tiled layout. Selecting another pane
 # without -Z unzooms, while -Z transfers zoom to the selected pane.
-layout=$($TMUX display-message -p -t P:0 '#{window_layout}')
+layout=$(pane_layout P:0)
 check_ok select-pane -t "$p0"
 check_ok resize-pane -Z -t "$p0"
 check_ok select-pane -t "$p2"
 check_fmt "$p2" '#{window_zoomed_flag}:#{pane_active}' '0:1'
-check_fmt P:0 '#{window_layout}' "$layout"
+check_layout P:0 "$layout"
 
 check_ok select-pane -t "$p0"
 check_ok resize-pane -Z -t "$p0"
@@ -322,7 +341,7 @@ check_ok select-pane -Z -t "$p2"
 check_fmt "$p2" '#{window_zoomed_flag}:#{pane_zoomed_flag}:#{pane_active}' \
 	'1:1:1'
 check_ok resize-pane -Z -t "$p2"
-check_fmt P:0 '#{window_layout}' "$layout"
+check_layout P:0 "$layout"
 
 # Directional selection temporarily restores the full layout to find its
 # neighbour, then follows the same unzoom or -Z transfer rules.
@@ -340,7 +359,7 @@ check_ok select-pane -D -Z -t "$p0"
 check_fmt "$p2" '#{window_zoomed_flag}:#{pane_zoomed_flag}:#{pane_active}' \
 	'1:1:1'
 check_ok resize-pane -Z -t "$p2"
-check_fmt P:0 '#{window_layout}' "$layout"
+check_layout P:0 "$layout"
 
 # The last-pane path has separate zoom handling, both with and without -Z.
 check_ok select-pane -t "$p0"
@@ -357,7 +376,7 @@ check_ok select-pane -l -Z -t P:0
 check_fmt "$p0" '#{window_zoomed_flag}:#{pane_zoomed_flag}:#{pane_active}' \
 	'1:1:1'
 check_ok resize-pane -Z -t "$p0"
-check_fmt P:0 '#{window_layout}' "$layout"
+check_layout P:0 "$layout"
 
 # Killing either a hidden ordinary pane or the zoom target unzooms.
 check_ok new-window -d -t P:12 -n zoom-kill 'cat'

regress/popup-drag-wide-character.sh

@@ -0,0 +1,126 @@
+#!/bin/sh
+
+# Damage at a popup edge must redraw complete grid characters. Drawing only a
+# wide character's base or padding cell leaves a two-cell hole behind.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lpopup-wide-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lpopup-wide-outer-$$ -f/dev/null"
+EMITTER=$DIR/emitter.pl
+BASE=$DIR/base
+CAPTURE=$DIR/capture
+POPUP_PID=
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	[ -n "$POPUP_PID" ] && kill "$POPUP_PID" 2>/dev/null
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+wait_old_rows_restored()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		sed -n '3,5p' "$BASE" >"$DIR/want"
+		sed -n '3,5p' "$CAPTURE" >"$DIR/got"
+		cmp -s "$DIR/want" "$DIR/got" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "wide characters under the old popup edge were not restored"
+}
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t outer:0.0 -l "$sequence" || exit 1
+	sleep 0.1
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+binmode STDOUT, ':encoding(UTF-8)';
+$| = 1;
+for my $row (1 .. 10) {
+	print "\e[$row;1H", chr(0x754c) x 20;
+}
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 40 -y 10 "perl '$EMITTER'" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 10 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lpopup-wide-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_client
+wait_outer_has '界界界'
+$OUTER capture-pane -p -t outer:0.0 >"$BASE" || exit 1
+
+$INNER display-popup -t "$CLIENT" -x 5 -y 5 -w 10 -h 3 -E \
+    "sh -c 'printf POPUP; exec sleep 100'" &
+POPUP_PID=$!
+wait_outer_has POPUP
+
+# The first motion starts the drag; the second moves the popup away from its
+# old rectangle. Its odd x coordinate bisects the underlying double-width
+# cells at both edges.
+mouse 0 10 3 M
+mouse 32 11 3 M
+mouse 32 28 7 M
+mouse 0 28 7 m
+wait_old_rows_restored
+
+exit 0

regress/prompt-words-history.sh

@@ -131,6 +131,14 @@ printf '%s\n' "$captured" | grep -Fq 'show-buffer' ||
 printf '%s\n' "$captured" | grep -Fq 'show-environment' ||
 	fail "ambiguous completion list was incomplete"
 $OUTER send-keys Escape || exit 1
+# Wait until Escape has closed the prompt before sending another Meta key.
+# Otherwise the two can be parsed together as a single escape sequence.
+i=0
+while capture | grep -Fq '(word)'; do
+	[ "$i" -lt 50 ] || fail "completion prompt did not close"
+	sleep 0.1
+	i=$((i + 1))
+done
 
 # Add entries to both history rings through real prompts.
 bind_prompt 'history-command'

regress/redraw-damage-accumulate.sh

@@ -0,0 +1,113 @@
+#!/bin/sh
+
+# Many wrapped rows crossing a panned viewport produce disjoint damage.
+# Every row must survive the rectangle-count limit and subsequent merging.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Laccumulate-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Laccumulate-outer-$$ -f/dev/null"
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+wait_marker()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$DIR/capture" || exit 1
+		grep -q "$1" "$DIR/capture" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "client did not receive $1"
+}
+cat >"$DIR/emitter.pl" <<'PERL'
+use strict;
+use warnings;
+$| = 1;
+for my $row (1 .. 80) {
+	printf "\e[%d;1HROW%02d-%s", $row, $row, 'abcdefghij' x 6;
+}
+print "\e[1;1H";
+while (!-e $ENV{TRIGGER}) {
+	select undef, undef, undef, 0.01;
+}
+my $output = '';
+# Each wrapped second row needs a separate damage rectangle. Keep the
+# batch below the PTY read size so all 18 arrive in the same input pass.
+for my $region (0 .. 17) {
+	my $top = 1 + $region * 4;
+	$output .= "\e[$top;1H" . ('A' x 80) . ('B' x 24) .
+	    sprintf('DAMAGE%02d', $region) . ('B' x 48);
+}
+$output .= "\e[80;21HDONE";
+syswrite STDOUT, $output;
+while (!-e "$ENV{TRIGGER}-merge") {
+	select undef, undef, undef, 0.01;
+}
+# Returning from the alternate screen requests a full-pane rectangle. A
+# later wrapped-row rectangle overlaps it and must not shrink that damage.
+$output = "\e[?1049h\e[40;21HALT-VISIBLE\e[?1049l";
+$output .= "\e[1;1H" . ('C' x 80) . ('D' x 24) . 'MERGE00' . ('D' x 49);
+$output .= "\e[80;21HMERGED";
+syswrite STDOUT, $output;
+sleep 100;
+PERL
+$INNER new-session -d -s inner -x 80 -y 80 \
+    "TRIGGER='$DIR/trigger' perl '$DIR/emitter.pl'" || exit 1
+$INNER set -g status off || exit 1
+$INNER set -g window-size manual || exit 1
+$INNER set -g automatic-rename off || exit 1
+$INNER set -g status-interval 0 || exit 1
+$INNER set -as terminal-features ',screen:sync' || exit 1
+$INNER set -g pane-border-lines simple || exit 1
+$OUTER new-session -d -s outer -x 40 -y 80 'sleep 100' || exit 1
+$OUTER set -g status off || exit 1
+$OUTER set -g window-size manual || exit 1
+$OUTER set -g default-terminal screen || exit 1
+$OUTER respawn-pane -k -t outer:0.0 "$INNER attach -t inner" || exit 1
+wait_marker ROW80
+CLIENT=$($OUTER display -p -t outer:0.0 '#{pane_tty}') || exit 1
+$INNER refresh-client -t "$CLIENT" -R 20 || exit 1
+# Keep the emitter inactive so its writes use a synchronized frame. Otherwise
+# its own queued output can force a full redraw and hide lost rectangles.
+$INNER new-pane -x 6 -y 3 -X 65 -Y 74 'sleep 100' || exit 1
+sleep 0.2
+: >"$DIR/trigger"
+wait_marker DONE
+sleep 0.2
+$OUTER capture-pane -p -t outer:0.0 >"$DIR/before" || exit 1
+region=0
+while [ "$region" -lt 18 ]; do
+	marker=$(printf 'DAMAGE%02d' "$region")
+	sed -n "$((2 + region * 4))p" "$DIR/before" | grep -q "$marker" ||
+	    fail "missing damage for region $region"
+	region=$((region + 1))
+done
+$INNER refresh-client -t "$CLIENT" || exit 1
+sleep 0.2
+$OUTER capture-pane -p -t outer:0.0 >"$DIR/after" || exit 1
+diff -u "$DIR/before" "$DIR/after" || fail "accumulated redraw differs from full redraw"
+: >"$DIR/trigger-merge"
+wait_marker MERGED
+sleep 0.2
+$OUTER capture-pane -p -t outer:0.0 >"$DIR/before" || exit 1
+sed -n '2p' "$DIR/before" | grep -q MERGE00 || fail "merged damage lost the wrapped row"
+$INNER refresh-client -t "$CLIENT" || exit 1
+sleep 0.2
+$OUTER capture-pane -p -t outer:0.0 >"$DIR/after" || exit 1
+diff -u "$DIR/before" "$DIR/after" || fail "merged redraw differs from full redraw"
+exit 0

regress/redraw-damage-blocked-client.sh

@@ -0,0 +1,140 @@
+#!/bin/sh
+
+# One terminal stops reading while another consumes floating-pane damage.
+# The slow client must catch up after the window's shared damage is cleared.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lblocked-inner-$$ -f/dev/null"
+FAST="$TEST_TMUX -Lblocked-fast-$$ -f/dev/null"
+SLOW="$TEST_TMUX -Lblocked-slow-$$ -f/dev/null"
+STOPPED=
+cleanup()
+{
+	[ -n "$STOPPED" ] && kill -CONT "$STOPPED" 2>/dev/null
+	$FAST kill-server 2>/dev/null
+	$SLOW kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+wait_marker()
+{
+	terminal=$1
+	marker=$2
+	i=0
+	while [ "$i" -lt 100 ]; do
+		$terminal capture-pane -p >"$DIR/capture" || exit 1
+		grep -q "$marker" "$DIR/capture" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "client did not receive $marker"
+}
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$FAST send-keys -l "$sequence" || exit 1
+	sleep 0.2
+}
+cat >"$DIR/emitter.pl" <<'PERL'
+use strict;
+use warnings;
+$| = 1;
+print 'READY';
+while (!-e "$ENV{TRIGGER}-flood") {
+	select undef, undef, undef, 0.01;
+}
+my $frame = 0;
+while (!-e "$ENV{TRIGGER}-stop") {
+	my $output = '';
+	for my $row (1 .. 20) {
+		$output .= "\e[$row;1H" . join('', map { chr(33 + ($_ + $frame) % 80) } 0 .. 77);
+	}
+	print $output;
+	$frame++;
+	select undef, undef, undef, 0.01;
+}
+for my $row (1 .. 20) {
+	printf "\e[%d;1HFINAL%02d-%s", $row, $row, '0123456789' x 7;
+}
+print "\e[20;1HDONE";
+sleep 100;
+PERL
+$INNER new-session -d -s inner -x 160 -y 80 \
+    "TRIGGER='$DIR/trigger' perl '$DIR/emitter.pl'" || exit 1
+$INNER set -g status off || exit 1
+$INNER set -g window-size manual || exit 1
+$INNER set -g automatic-rename off || exit 1
+$INNER set -g status-interval 0 || exit 1
+$INNER set -g mouse on || exit 1
+$INNER set -g pane-border-lines simple || exit 1
+FLOAT=$($INNER new-pane -PF '#{pane_id}' -x 16 -y 5 -X 5 -Y 5 \
+    'printf FLOAT; exec sleep 100') || exit 1
+for terminal in "$FAST" "$SLOW"; do
+	$terminal new-session -d -x 160 -y 80 'sleep 100' || exit 1
+	$terminal set -g status off || exit 1
+	$terminal set -g window-size manual || exit 1
+	$terminal set -g default-terminal screen || exit 1
+	$terminal respawn-pane -k "$INNER attach -t inner" || exit 1
+	wait_marker "$terminal" READY
+done
+FASTCLIENT=$($FAST display -p '#{pane_tty}') || exit 1
+SLOWCLIENT=$($SLOW display -p '#{pane_tty}') || exit 1
+SLOWPID=$($SLOW display -p '#{pid}') || exit 1
+before=$($INNER display -p -c "$FASTCLIENT" '#{client_written}') || exit 1
+slowbefore=$($INNER display -p -c "$SLOWCLIENT" '#{client_written}') || exit 1
+# The large terminal keeps this backlog below the discard threshold, so
+# automatic recovery from discarded output cannot mask lost damage.
+# Stop only our outer server, leaving its inner client attached to a PTY
+# whose master is no longer read. This creates real terminal backpressure.
+STOPPED=$SLOWPID
+kill -STOP "$SLOWPID" || exit 1
+: >"$DIR/trigger-flood"
+i=0
+while :; do
+	written=$($INNER display -p -c "$SLOWCLIENT" '#{client_written}') || exit 1
+	fastwritten=$($INNER display -p -c "$FASTCLIENT" '#{client_written}') || exit 1
+	# More than a PTY can buffer has been queued for the stopped terminal,
+	# while the other terminal is still receiving the same output.
+	[ "$written" -gt "$((slowbefore + 65536))" ] &&
+	    [ "$fastwritten" -gt "$((before + 65536))" ] && break
+	[ "$i" -lt 100 ] || fail "slow client did not become blocked"
+	sleep 0.1
+	i=$((i + 1))
+done
+: >"$DIR/trigger-stop"
+wait_marker "$FAST" DONE
+[ "$($INNER display -p -c "$FASTCLIENT" '#{client_discarded}')" -eq 0 ] ||
+    fail "fast client also became blocked"
+mouse 0 12 6 M
+mouse 32 42 6 M
+mouse 0 42 6 m
+[ "$($INNER display -p -t "$FLOAT" '#{pane_left}')" -eq 36 ] || fail "pane did not move"
+$FAST capture-pane -p >"$DIR/fast-before" || exit 1
+# Ensure the fast client already restored the vacated frame.
+sed -n '6p' "$DIR/fast-before" | grep -q '^FINAL06-0123456789' ||
+    fail "fast client did not restore old footprint"
+kill -CONT "$SLOWPID" || exit 1
+STOPPED=
+wait_marker "$SLOW" DONE
+# Allow queued terminal output and deferred redraws to drain.
+sleep 0.5
+[ "$($INNER display -p -c "$SLOWCLIENT" '#{client_discarded}')" -eq 0 ] ||
+    fail "discard recovery could mask lost deferred damage"
+$SLOW capture-pane -p >"$DIR/slow-before" || exit 1
+diff -u "$DIR/fast-before" "$DIR/slow-before" || fail "slow client did not catch up"
+$INNER refresh-client -t "$FASTCLIENT" || exit 1
+sleep 0.2
+$FAST capture-pane -p >"$DIR/after" || exit 1
+diff -u "$DIR/fast-before" "$DIR/after" || fail "damage redraw differed from full redraw"
+exit 0

regress/redraw-damage-only.sh

@@ -0,0 +1,112 @@
+#!/bin/sh
+
+# Check a redraw callback which has no accompanying client redraw flags. A
+# wrapped row crossing a panned viewport cannot use the direct tty path.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Ldamage-only-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Ldamage-only-outer-$$ -f/dev/null"
+EMITTER=$DIR/emitter.pl
+TRIGGER=$DIR/trigger
+CAPTURE=$DIR/capture
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+wait_inner_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$INNER capture-pane -p -t inner:0.0 2>/dev/null |
+		    grep -q "$marker" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner pane did not contain $marker"
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+$| = 1;
+for my $row (1 .. 12) {
+	print "\e[$row;1H", 'o' x 79;
+}
+print "\e[1;1H";
+while (!-e $ENV{TRIGGER}) {
+	select undef, undef, undef, 0.01;
+}
+
+my $second = ('B' x 24) . 'DAMAGE-ONLY' . ('B' x 45);
+print "\e[5;1H", ('A' x 80), $second;
+sleep 100;
+PERL
+
+$INNER new-session -d -s inner -x 80 -y 12 \
+    "TRIGGER='$TRIGGER' perl '$EMITTER'" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 12 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Ldamage-only-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_client
+$INNER refresh-client -t "$CLIENT" -R 20 || exit 1
+wait_outer_has oooooooooo
+
+: >"$TRIGGER"
+wait_inner_has DAMAGE-ONLY
+wait_outer_has DAMAGE-ONLY
+
+exit 0

regress/redraw-damage-viewports.sh

@@ -0,0 +1,112 @@
+#!/bin/sh
+
+# Moving and interactively resizing floating panes must restore both clients,
+# including a smaller client panned horizontally and vertically.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lviewports-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lviewports-outer-$$ -f/dev/null"
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t wide:0.0 -l "$sequence" || exit 1
+	sleep 0.2
+}
+assert_scene()
+{
+	# Compare what each terminal actually received with a fresh full redraw.
+	# Capture both first: refreshing one client must not repair the other.
+	for target in wide small; do
+		$OUTER capture-pane -p -t "$target:0.0" >"$DIR/$target-before" || exit 1
+	done
+	$INNER refresh-client -t "$WIDE" || exit 1
+	$INNER refresh-client -t "$SMALL" || exit 1
+	sleep 0.2
+	for target in wide small; do
+		$OUTER capture-pane -p -t "$target:0.0" >"$DIR/$target-after" || exit 1
+		diff -u "$DIR/$target-before" "$DIR/$target-after" ||
+		    fail "$1: $target client differed from a full redraw"
+	done
+}
+
+cat >"$DIR/background.pl" <<'PERL'
+$| = 1;
+for my $row (1 .. 24) {
+	printf "\e[%d;1HROW%02d-", $row, $row;
+	print '0123456789' x 7;
+}
+sleep 100;
+PERL
+$INNER new-session -d -s inner -x 80 -y 24 "perl '$DIR/background.pl'" || exit 1
+$INNER set -g status off || exit 1
+$INNER set -g window-size manual || exit 1
+$INNER set -g automatic-rename off || exit 1
+$INNER set -g status-interval 0 || exit 1
+$INNER set -g mouse on || exit 1
+$INNER set -g default-command 'sleep 100' || exit 1
+$INNER set -g pane-border-lines simple || exit 1
+$OUTER new-session -d -s wide -x 80 -y 24 'sleep 100' || exit 1
+$OUTER set -g status off || exit 1
+$OUTER set -g window-size manual || exit 1
+$OUTER set -g default-terminal screen || exit 1
+$OUTER new-session -d -s small -x 40 -y 12 'sleep 100' || exit 1
+for target in wide small; do
+	$OUTER respawn-pane -k -t "$target:0.0" "$INNER attach -t inner" || exit 1
+done
+i=0
+while [ "$($INNER list-clients | wc -l)" -ne 2 ]; do
+	[ "$i" -lt 50 ] || fail "two clients did not attach"
+	sleep 0.1
+	i=$((i + 1))
+done
+WIDE=$($OUTER display -p -t wide:0.0 '#{pane_tty}') || exit 1
+SMALL=$($OUTER display -p -t small:0.0 '#{pane_tty}') || exit 1
+$INNER refresh-client -t "$SMALL" -R 20 || exit 1
+$INNER refresh-client -t "$SMALL" -D 6 || exit 1
+FLOAT=$($INNER new-pane -d -PF '#{pane_id}' -x 16 -y 6 -X 25 -Y 9) || exit 1
+sleep 0.3
+assert_scene initial
+# Confirm that the two clients really have different viewports.
+[ "$(head -1 "$DIR/wide-before" | cut -c1-6)" = ROW01- ] || fail "wrong wide viewport"
+[ "$(head -1 "$DIR/small-before" | cut -c1-6)" != ROW01- ] || fail "small client was not panned"
+
+# Meta-drag the body using move-pane -M, including a partially clipped position.
+mouse 8 30 12 M
+mouse 40 48 15 M
+[ "$($INNER display -p -t "$FLOAT" '#{pane_left}')" -eq 44 ] || fail "Meta-drag did not move pane"
+assert_scene move-right
+mouse 40 28 10 M
+assert_scene move-back
+mouse 8 28 10 m
+
+# Ctrl-drag creates a new floating pane, then changes its size while held.
+mouse 16 52 14 M
+mouse 48 75 23 M
+NEW=$($INNER display -p '#{pane_id}') || exit 1
+[ "$NEW" != "$FLOAT" ] || fail "Ctrl-drag did not create a pane"
+[ "$($INNER display -p -t "$NEW" '#{pane_floating_flag}')" -eq 1 ] || fail "new pane is not floating"
+assert_scene create
+mouse 48 64 19 M
+[ "$($INNER display -p -t "$NEW" '#{pane_width}')" -eq 11 ] || fail "Ctrl-drag did not shrink pane"
+assert_scene shrink
+mouse 16 64 19 m
+assert_scene release
+exit 0

regress/redraw-multiclient.sh

@@ -0,0 +1,186 @@
+#!/bin/sh
+
+# Redraw a moved floating pane on both attached clients viewing the same
+# window. Window redraw work must not be consumed by only one client.
+#
+# Uses ASCII pane borders (rather than the default UTF-8 box-drawing) because
+# this test nests a real tmux client inside another tmux's pane to get a
+# genuine terminal to capture from; that nested-tmux relay has been observed
+# to mis-render a cell that previously held a multi-byte UTF-8 border
+# character being overwritten later by plain content, on the outer instance's
+# own interpretation, independent of anything the inner tmux sends. That is a
+# nested-test-harness artifact, not a real tmux bug - confirmed by replaying
+# the exact same drag sequence against a real terminal (xterm), where it
+# never reproduces. ASCII borders avoid the artifact entirely.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lredraw-multi-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lredraw-multi-outer-$$ -f/dev/null"
+CAPTURE=$DIR/capture
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_clients()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		count=$($INNER list-clients 2>/dev/null | wc -l)
+		[ "$count" -eq 2 ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "two inner clients did not attach"
+}
+
+wait_outer_has()
+{
+	target=$1
+	marker=$2
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t "$target" >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer pane $target did not show $marker"
+}
+
+wait_float_left()
+{
+	comparison=$1
+	limit=$2
+	i=0
+	while [ "$i" -lt 50 ]; do
+		left=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+		if [ "$comparison" = gt ] && [ "$left" -gt "$limit" ]; then
+			return 0
+		fi
+		if [ "$comparison" = lt ] && [ "$left" -lt "$limit" ]; then
+			return 0
+		fi
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "floating pane did not move"
+}
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$2" "$3" "$4" "$5")
+	$OUTER send-keys -t "$1" -l "$sequence" || exit 1
+	sleep 0.1
+}
+
+drag_float()
+{
+	target=$1
+	startcol=$2
+	startrow=$3
+	endcol=$4
+	mouse "$target" 0 "$startcol" "$startrow" M
+	mouse "$target" 32 "$endcol" "$startrow" M
+	mouse "$target" 0 "$endcol" "$startrow" m
+}
+
+assert_scene()
+{
+	target=$1
+	base=$2
+	firstcol=$3
+	lastcol=$4
+
+	$OUTER capture-pane -p -t "$target" >"$CAPTURE" || exit 1
+
+	# With ASCII (simple) borders every corner and junction is the same
+	# '+', so one rectangular floating pane always draws exactly 4 of
+	# them; more means a stale frame was left behind somewhere.
+	corners=$(grep -o '+' "$CAPTURE" | wc -l)
+	[ "$corners" -eq 4 ] ||
+	    fail "outer pane $target had $corners floating frames"
+
+	sed -n '6,11p' "$base" | cut -c"$firstcol-$lastcol" >"$DIR/want"
+	sed -n '6,11p' "$CAPTURE" | cut -c"$firstcol-$lastcol" >"$DIR/got"
+	cmp -s "$DIR/want" "$DIR/got" ||
+	    fail "outer pane $target did not restore the old floating area"
+}
+
+C="sh -c 'i=0; while [ \$i -lt 20 ]; do printf \"\\033[%d;1HBG-ROW-%02d-abcdefghijklmnopqrstuvwxyz0123456789\" \$((i + 1)) \$i; i=\$((i + 1)); done; exec sleep 100'"
+
+$INNER new-session -d -s inner -x 60 -y 20 "$C" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+$INNER set-option -g default-command 'sleep 100' || exit 1
+$INNER set-option -g pane-border-lines simple || exit 1
+
+$OUTER new-session -d -s outer -x 121 -y 20 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen || exit 1
+$OUTER split-window -h -t outer:0.0 'sleep 100' || exit 1
+
+PANES=$($OUTER list-panes -t outer:0 -F '#{pane_id} #{pane_left}')
+LEFT=$(echo "$PANES" | sort -k2 -n | head -1 | cut -d' ' -f1)
+RIGHT=$(echo "$PANES" | sort -k2 -n | tail -1 | cut -d' ' -f1)
+[ -n "$LEFT" ] && [ -n "$RIGHT" ] || fail "could not find outer panes"
+
+$OUTER respawn-pane -k -t "$LEFT" \
+    "$TEST_TMUX -Lredraw-multi-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+$OUTER respawn-pane -k -t "$RIGHT" \
+    "$TEST_TMUX -Lredraw-multi-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_for_clients
+wait_outer_has "$LEFT" BG-ROW-19
+wait_outer_has "$RIGHT" BG-ROW-19
+$OUTER capture-pane -p -t "$LEFT" >"$DIR/base-left" || exit 1
+$OUTER capture-pane -p -t "$RIGHT" >"$DIR/base-right" || exit 1
+
+FLOAT=$($INNER new-pane -dPF '#{pane_id}' -x 16 -y 5 -X 5 -Y 5) ||
+    fail "could not create floating pane"
+wait_outer_has "$LEFT" '+'
+wait_outer_has "$RIGHT" '+'
+
+FTOP=$($INNER display-message -p -t "$FLOAT" '#{pane_top}')
+FLEFT=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+FWIDTH=$($INNER display-message -p -t "$FLOAT" '#{pane_width}')
+GRABCOL=$((FLEFT + FWIDTH / 2 + 1))
+
+# Move right through one client and require both clients to restore the old
+# left-hand footprint.
+drag_float "$LEFT" "$GRABCOL" "$FTOP" $((GRABCOL + 30))
+wait_float_left gt 30
+assert_scene "$LEFT" "$DIR/base-left" 1 20
+assert_scene "$RIGHT" "$DIR/base-right" 1 20
+
+# Move back through the other client and check the old right-hand footprint.
+FLEFT=$($INNER display-message -p -t "$FLOAT" '#{pane_left}')
+GRABCOL=$((FLEFT + FWIDTH / 2 + 1))
+drag_float "$RIGHT" "$GRABCOL" "$FTOP" $((GRABCOL - 30))
+wait_float_left lt 10
+assert_scene "$LEFT" "$DIR/base-left" 35 60
+assert_scene "$RIGHT" "$DIR/base-right" 35 60
+
+exit 0

regress/redraw-screen-write.sh

@@ -0,0 +1,208 @@
+#!/bin/sh
+
+# Check that full and region screen-write fallbacks update an attached client,
+# not only tmux's internal pane grid.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+EMITTER=$DIR/emitter.pl
+CAPTURE=$DIR/capture
+INNER=
+OUTER=
+N=0
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	[ -n "$OUTER" ] && $OUTER kill-server 2>/dev/null
+	[ -n "$INNER" ] && $INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+wait_outer_lacks()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" || return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client still showed $marker"
+}
+
+wait_inner_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$INNER capture-pane -p -t inner:0.0 2>/dev/null |
+		    grep -q "$marker" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner pane did not contain $marker"
+}
+
+wait_inner_lacks()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$INNER capture-pane -p -t inner:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" || return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner pane still contained $marker"
+}
+
+setup()
+{
+	mode=$1
+	[ -n "$OUTER" ] && $OUTER kill-server 2>/dev/null
+	[ -n "$INNER" ] && $INNER kill-server 2>/dev/null
+	N=$((N + 1))
+	INNER="$TEST_TMUX -Lredraw-write-inner-$$-$N -f/dev/null"
+	OUTER="$TEST_TMUX -Lredraw-write-outer-$$-$N -f/dev/null"
+
+	$INNER new-session -d -s inner -x 40 -y 12 \
+	    "MODE=$mode READY='$DIR/ready-$N' TRIGGER='$DIR/trigger-$N' perl '$EMITTER'" ||
+	    exit 1
+	$INNER set-option -g status off || exit 1
+	$INNER set-option -g window-size manual || exit 1
+
+	$OUTER new-session -d -s outer -x 40 -y 12 'sleep 100' || exit 1
+	$OUTER set-option -g status off || exit 1
+	$OUTER set-option -g window-size manual || exit 1
+	$OUTER set-option -g default-terminal screen || exit 1
+	$OUTER respawn-pane -k -t outer:0.0 \
+	    "$TEST_TMUX -Lredraw-write-inner-$$-$N -f/dev/null attach-session -t inner" ||
+	    exit 1
+}
+
+trigger()
+{
+	: >"$DIR/trigger-$N-${1:-1}"
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+$| = 1;
+my $mode = $ENV{MODE};
+my $ready = $ENV{READY};
+my $trigger = $ENV{TRIGGER};
+
+sub fill_screen {
+	my ($prefix) = @_;
+	print "\e[2J\e[H";
+	for my $row (0 .. 11) {
+		printf "\e[%d;1H%s-ROW-%02d", $row + 1, $prefix, $row;
+	}
+}
+
+if ($mode eq 'ris') {
+	fill_screen('RIS');
+} elsif ($mode eq 'alternate') {
+	fill_screen('BASE');
+} elsif ($mode eq 'scroll') {
+	fill_screen('SCROLL');
+} else {
+	die "unknown mode $mode\n";
+}
+
+open my $fh, '>', $ready or die "$ready: $!\n";
+close $fh;
+while (!-e "$trigger-1") {
+	select undef, undef, undef, 0.01;
+}
+
+if ($mode eq 'ris') {
+	print "\ec";
+} elsif ($mode eq 'alternate') {
+	print "\e[?1049h";
+	fill_screen('ALT');
+	while (!-e "$trigger-2") {
+		select undef, undef, undef, 0.01;
+	}
+	print "\e[?1049l";
+} else {
+	print "\e[12;1H\r\nSCROLL-NEW";
+}
+sleep 100;
+PERL
+
+# RIS clears the complete screen. The source pane and attached client must both
+# lose every old row.
+setup ris
+wait_outer_has RIS-ROW-11
+trigger
+wait_inner_lacks RIS-ROW
+wait_outer_lacks RIS-ROW
+
+# Leaving the alternate screen restores every row of the base screen.
+setup alternate
+wait_outer_has BASE-ROW-11
+trigger
+wait_inner_has ALT-ROW-11
+wait_outer_has ALT-ROW-11
+wait_outer_lacks BASE-ROW
+trigger 2
+wait_inner_has BASE-ROW-11
+wait_outer_has BASE-ROW-11
+wait_outer_lacks ALT-ROW
+
+# Scrolling a pane which is narrower than the terminal redraws its complete
+# region. Check the physical client row by row after the source grid shifts.
+setup scroll
+$INNER split-window -h -t inner:0 'sleep 100' || exit 1
+wait_outer_has SCROLL-ROW-11
+trigger
+wait_inner_has SCROLL-NEW
+wait_outer_has SCROLL-NEW
+row=1
+while [ "$row" -le 11 ]; do
+	expected=$(printf 'SCROLL-ROW-%02d' "$row")
+	actual=$(sed -n "${row}p" "$CAPTURE")
+	case "$actual" in
+	"$expected"*) ;;
+	*) fail "outer row $row was not redrawn as $expected" ;;
+	esac
+	row=$((row + 1))
+done
+actual=$(sed -n '12p' "$CAPTURE")
+case "$actual" in
+SCROLL-NEW*) ;;
+*) fail "outer bottom row was not redrawn as SCROLL-NEW" ;;
+esac
+
+exit 0

regress/respawn-pane-control-lag.sh

@@ -15,7 +15,7 @@ PATH=/bin:/usr/bin
 TERM=screen
 
 [ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX="$TEST_TMUX -Ltest"
+TMUX="$TEST_TMUX -Ltest$$"
 $TMUX kill-server 2>/dev/null
 
 DIR=$(mktemp -d)

regress/run-shell-cwd.sh

@@ -0,0 +1,55 @@
+#!/bin/sh
+
+# run-shell -c should expand formats using the target pane.
+
+PATH=/bin:/usr/bin
+TERM=screen
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+
+TMP=$(mktemp -d)
+trap '$TMUX kill-server 2>/dev/null; rm -rf "$TMP"' 0 1 15
+TMP=$(cd "$TMP" && pwd -P)
+mkdir "$TMP/first" "$TMP/second dir" || exit 1
+
+check_directory()
+{
+	actual=$(cat "$TMP/out")
+	if [ "$actual" != "$1" ]; then
+		echo "Expected directory '$1', got '$actual'"
+		exit 1
+	fi
+}
+
+# The start path is available immediately, before the child is scheduled.
+# Use it to test the format context in the same command queue as creation.
+$TMUX new-session -d -s test -c "$TMP/first" 'sleep 60' \; \
+	 run-shell -c '#{pane_start_path}' "pwd >'$TMP/out'" || exit 1
+check_directory "$TMP/first"
+
+# An explicit target must supply the format context, including with a delay.
+pane=$($TMUX new-window -d -P -F '#{pane_id}' -t test \
+	-c "$TMP/second dir" 'sleep 60') || exit 1
+# The current path depends on the operating system finding the child process.
+i=0
+while [ "$($TMUX display-message -p -t "$pane" '#{pane_current_path}')" != \
+    "$TMP/second dir" ]; do
+	if [ "$i" -ge 100 ]; then
+		echo "Timed out waiting for pane current directory"
+		exit 1
+	fi
+	sleep 0.05
+	i=$((i + 1))
+done
+$TMUX run-shell -t "$pane" -d 0.1 -c '#{pane_current_path}' \
+	"pwd >'$TMP/out'" || exit 1
+check_directory "$TMP/second dir"
+
+# Literal directories and the default client directory still work.
+$TMUX run-shell -c "$TMP/second dir" "pwd >'$TMP/out'" || exit 1
+check_directory "$TMP/second dir"
+(cd "$TMP/first" && $TMUX run-shell "pwd >'$TMP/out'") || exit 1
+check_directory "$TMP/first"
+
+exit 0

regress/screen-redraw-floating.sh

@@ -107,6 +107,12 @@ $TMUX2 new-pane -x28 -y8 -X4 -Y1 -B double \
 	"sh -c 'printf FLOAT; exec sleep 100'" || exit 1
 compare floating-border-double
 
+# Larger floating pane with rounded border lines.
+new_scene 40 12
+$TMUX2 new-pane -x28 -y8 -X4 -Y1 -B rounded \
+	"sh -c 'printf FLOAT; exec sleep 100'" || exit 1
+compare floating-border-rounded
+
 # Floating pane with no border lines: redraw_mark_pane_borders returns early so
 # the float has no border at all, only its (clipped) content over the base pane.
 new_scene 40 12

regress/screen-redraw-menus.sh

@@ -106,9 +106,28 @@ compare menu-over-split
 
 # Menu with no border lines.
 setup 40 14
-menu -b none -x6 -y8
+$TMUX2 display-menu -T "This title must not reserve width" -C 1 \
+    -b none -x6 -y8 \
+    "Alpha item" a "" \
+    "Beta item" b "" \
+    "" "" "" \
+    "Gamma item" g "" || exit 1
+sleep 1
 compare menu-noborder
 
+# Menu border style follows the explicitly targeted window, not the current
+# window when a different pane is selected.
+setup 40 14
+$TMUX2 set menu-border-lines none || exit 1
+$TMUX2 neww || exit 1
+$TMUX2 display-menu -t%0 -T "Menu" -C 1 \
+    "Alpha item" a "" \
+    "Beta item" b "" \
+    "" "" "" \
+    "Gamma item" g "" || exit 1
+$TMUX2 selectw -t%0 || exit 1
+compare menu-target-window-noborder
+
 # Menu with double border lines.
 setup 40 14
 menu -b double -x6 -y8

regress/screen-redraw-popups.sh

@@ -1,101 +0,0 @@
-#!/bin/sh
-
-# Exercise drawing of popups (display-popup) over the window scene. A popup is an
-# overlay drawn on top of the redraw scene (the overlay_draw path in
-# screen-redraw.c), so this guards against regressions in how popups appear.
-#
-# A popup is modal and stays open until its command exits, so each scene fully
-# re-creates the servers and re-attaches; the popup is opened in the background
-# (display-popup blocks the client that runs it) and the outer pane is captured
-# while it is open.
-#
-# Run with GENERATE=1 to (re)create the golden files.
-
-PATH=/bin:/usr/bin
-TERM=screen
-LC_ALL=C.UTF-8
-export TERM LC_ALL
-
-[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
-TMUX=
-TMUX2=
-SETUP=0
-RESULTS=screen-redraw-results
-
-TMP=$(mktemp)
-
-cleanup() {
-	rm -f "$TMP"
-	[ -n "$TMUX" ] && $TMUX kill-server 2>/dev/null
-	[ -n "$TMUX2" ] && $TMUX2 kill-server 2>/dev/null
-}
-trap cleanup 0 1 15
-
-fail() {
-	echo "$*" >&2
-	exit 1
-}
-
-compare() {
-	sleep 1
-	$TMUX capturep -p >$TMP || exit 1
-	if [ -n "$GENERATE" ]; then
-		cp $TMP "$RESULTS/$1.result" || exit 1
-		echo "generated $1"
-	else
-		cmp -s $TMP "$RESULTS/$1.result" || \
-			fail "scene $1 differs from $RESULTS/$1.result"
-	fi
-}
-
-C="sh -c 'i=0; while [ \$i -lt 13 ]; do printf \"POP%02d abcdefghij\n\" \$i; i=\$((i + 1)); done; exec sleep 100'"
-
-# setup: fresh inner window attached inside a fresh outer pane, 40x14.
-setup() {
-	[ -n "$TMUX" ] && $TMUX kill-server 2>/dev/null
-	[ -n "$TMUX2" ] && $TMUX2 kill-server 2>/dev/null
-	SETUP=$((SETUP + 1))
-	TMUX="$TEST_TMUX -LtestA$$-$SETUP -f/dev/null"
-	TMUX2="$TEST_TMUX -LtestB$$-$SETUP -f/dev/null"
-	$TMUX2 new -d -x40 -y14 "$C" || exit 1
-	$TMUX2 set -g status off || exit 1
-	$TMUX2 set -g window-size manual || exit 1
-	$TMUX2 resizew -x40 -y14 || exit 1
-	$TMUX new -d -x40 -y14 || exit 1
-	$TMUX set -g status off || exit 1
-	$TMUX set -g window-size manual || exit 1
-	$TMUX set -g default-terminal "tmux-256color" || exit 1
-	$TMUX send -l "$TMUX2 attach" || exit 1
-	$TMUX send Enter || exit 1
-	sleep 1
-}
-
-# popup <args>: open a popup running a fixed command, in the background (it stays
-# open because the command sleeps; the servers are killed at the next setup).
-popup() {
-	$TMUX2 display-popup "$@" -E "sh -c 'printf POPUP; exec sleep 100'" &
-	sleep 1
-}
-
-# Basic popup over a single pane.
-setup
-popup -w20 -h6 -x6 -y3
-compare popup-basic
-
-# Popup over a split: drawn on top of the pane border.
-setup
-$TMUX2 splitw -h "$C" || exit 1
-popup -w24 -h8 -x8 -y3
-compare popup-over-split
-
-# Popup with no border lines (-B).
-setup
-popup -B -w20 -h6 -x6 -y3
-compare popup-noborder
-
-# Popup with double border lines.
-setup
-popup -b double -w20 -h6 -x6 -y3
-compare popup-double
-
-exit 0

regress/screen-redraw-results/floating-border-rounded.result

@@ -0,0 +1,12 @@
+base
+    ╭──────────────────────────╮
+    │FLOAT                     │
+    │                          │
+    │                          │
+    │                          │
+    │                          │
+    │                          │
+    ╰──────────────────────────╯
+
+
+

regress/screen-redraw-results/menu-noborder.result

@@ -1,11 +1,11 @@
 MENU00 abcdefghij
 MENU01 abcdefghij
-MENU02  Menu            
-MENU03  Alpha item (a)  
-MENU04  Beta item  (b)  
-MENU05                  
-MENU06  Gamma item (g)  
-MENU07                  
+MENU02 abcdefghij
+MENU03 abcdefghij
+MENU04 Alpha item (a) 
+MENU05 Beta item  (b) 
+MENU06                
+MENU07 Gamma item (g) 
 MENU08 abcdefghij
 MENU09 abcdefghij
 MENU10 abcdefghij

regress/screen-redraw-results/menu-target-window-noborder.result

@@ -0,0 +1,13 @@
+MENU00 abcdefghij
+MENU01 abcdefghij
+MENU02 abcdefghij
+MENU03 abcdefghij
+MENU04 abcd Alpha item (a) 
+MENU05 abcd Beta item  (b) 
+MENU06 abcd                
+MENU07 abcd Gamma item (g) 
+MENU08 abcdefghij
+MENU09 abcdefghij
+MENU10 abcdefghij
+MENU11 abcdefghij
+MENU12 abcdefghij

regress/screen-redraw-results/popup-basic.result

@@ -1,14 +0,0 @@
-POP00 ┌──────────────────┐
-POP01 │POPUP             │
-POP02 │                  │
-POP03 │                  │
-POP04 │                  │
-POP05 └──────────────────┘
-POP06 abcdefghij
-POP07 abcdefghij
-POP08 abcdefghij
-POP09 abcdefghij
-POP10 abcdefghij
-POP11 abcdefghij
-POP12 abcdefghij
-

regress/screen-redraw-results/popup-double.result

@@ -1,14 +0,0 @@
-POP00 ╔══════════════════╗
-POP01 ║POPUP             ║
-POP02 ║                  ║
-POP03 ║                  ║
-POP04 ║                  ║
-POP05 ╚══════════════════╝
-POP06 abcdefghij
-POP07 abcdefghij
-POP08 abcdefghij
-POP09 abcdefghij
-POP10 abcdefghij
-POP11 abcdefghij
-POP12 abcdefghij
-

regress/screen-redraw-results/popup-noborder.result

@@ -1,14 +0,0 @@
-POP00 POPUP
-POP01
-POP02
-POP03
-POP04
-POP05
-POP06 abcdefghij
-POP07 abcdefghij
-POP08 abcdefghij
-POP09 abcdefghij
-POP10 abcdefghij
-POP11 abcdefghij
-POP12 abcdefghij
-

regress/screen-redraw-results/popup-over-split.result

@@ -1,14 +0,0 @@
-POP00 ab┌──────────────────────┐fghij
-POP01 ab│POPUP                 │fghij
-POP02 ab│                      │fghij
-POP03 ab│                      │fghij
-POP04 ab│                      │fghij
-POP05 ab│                      │fghij
-POP06 ab│                      │fghij
-POP07 ab└──────────────────────┘fghij
-POP08 abcdefghij    │POP08 abcdefghij
-POP09 abcdefghij    │POP09 abcdefghij
-POP10 abcdefghij    │POP10 abcdefghij
-POP11 abcdefghij    │POP11 abcdefghij
-POP12 abcdefghij    │POP12 abcdefghij
-                    │

regress/screen-redraw-tiled.sh

@@ -95,7 +95,8 @@ layout_tee_down() {		# top/bottom, bottom split: a top tee
 $TMUX kill-server 2>/dev/null
 $TMUX2 kill-server 2>/dev/null
 
-$TMUX2 new -d -x40 -y14 "sh -c 'exec sleep 100'" || exit 1
+# Keep the anchor window alive until cleanup, even on slow test runs.
+$TMUX2 new -d -x40 -y14 'exec cat' || exit 1
 $TMUX2 set -g status off || exit 1
 $TMUX2 set -g window-size manual || exit 1
 $TMUX2 set -g pane-border-format " #{pane_index} " || exit 1

regress/switch-client-redraw.sh

@@ -0,0 +1,81 @@
+#!/bin/sh
+
+# Switching windows in the same session must redraw the attached client. The
+# session object is shared, so its current winlink cannot be compared after it
+# has already been changed.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lswitch-redraw-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lswitch-redraw-outer-$$ -f/dev/null"
+CAPTURE=$DIR/capture
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		CLIENT=$($INNER list-clients -F '#{client_name}' 2>/dev/null)
+		[ -n "$CLIENT" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "inner client did not attach"
+}
+
+wait_outer_has()
+{
+	marker=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+		grep -q "$marker" "$CAPTURE" && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "outer client did not show $marker"
+}
+
+$INNER new-session -d -s inner -x 40 -y 8 \
+    "printf '\033[2J\033[HA-WINDOW'; exec sleep 100" || exit 1
+$INNER new-window -d -t inner:1 \
+    "printf '\033[2J\033[HB-WINDOW'; exec sleep 100" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 8 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lswitch-redraw-inner-$$ -f/dev/null attach-session -t inner:0" ||
+    exit 1
+
+wait_for_client
+wait_outer_has A-WINDOW
+
+$INNER switch-client -c "$CLIENT" -t inner:1.0 || exit 1
+[ "$($INNER display-message -p -t inner '#{window_index}')" -eq 1 ] ||
+    fail "server did not select window 1"
+wait_outer_has B-WINDOW
+
+exit 0

regress/sync-output-wrapped.sh

@@ -0,0 +1,116 @@
+#!/bin/sh
+
+# When only some lines are redrawn after a synchronized update, a line
+# following a wrapped line must be drawn at its own position, not where the
+# cursor happens to be.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+TMUX_TMPDIR=$DIR
+export TMUX_TMPDIR
+
+INNER="$TEST_TMUX -Li$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lo$$ -f/dev/null"
+CONTROL=$DIR/control
+EMITTER=$DIR/emitter.pl
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+wait_for_file()
+{
+	i=0
+	while [ "$i" -lt 50 ] && [ ! -e "$1" ]; do
+		sleep 0.1
+		i=$((i + 1))
+	done
+	[ -e "$1" ] || fail "$2"
+}
+
+wait_for_client()
+{
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$INNER list-clients -F '#{client_termfeatures}' 2>/dev/null |
+		    grep -q 'sync' && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "sync-capable client did not attach"
+}
+
+cat >"$EMITTER" <<'PERL'
+use strict;
+use warnings;
+
+my $control = $ENV{CONTROL};
+(my $dir = $control) =~ s{/[^/]+$}{};
+
+# Fill the screen with 80 column lines and no newlines so every line wraps.
+my $out = "\e[H\e[2J";
+for my $row (1 .. 24) {
+	$out .= substr(sprintf("ROW%02d_", $row) . ('x' x 80), 0, 80);
+}
+syswrite STDOUT, $out . "\e[1;1H";
+
+open my $painted, '>', "$dir/painted" or die "$dir/painted: $!\n";
+close $painted;
+while (!-e $control) {
+	select undef, undef, undef, 0.01;
+}
+
+# Change rows 2 and 6 in one synchronized update.
+my $frame = "\e[?2026h" .
+    "\e[2;1H" . substr("NEW02_" . ('#' x 80), 0, 80) .
+    "\e[6;1H" . substr("NEW06_" . ('%' x 80), 0, 80) .
+    "\e[24;1H" .
+    "\e[?2026l";
+my $written = syswrite STDOUT, $frame;
+die "short synchronized frame write\n"
+    unless defined $written && $written == length $frame;
+open my $done, '>', "$dir/done" or die "$dir/done: $!\n";
+close $done;
+select undef, undef, undef, 3;
+PERL
+
+$INNER new-session -d -s inner -x 80 -y 24 \
+    "CONTROL='$CONTROL' perl '$EMITTER'" || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -as terminal-features '*:sync' || exit 1
+
+$OUTER new-session -d -s outer -x 80 -y 24 \
+    "$TEST_TMUX -Li$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+wait_for_client
+
+wait_for_file "$DIR/painted" "application did not paint"
+sleep 1
+: >"$CONTROL"
+wait_for_file "$DIR/done" "application did not finish"
+sleep 1
+
+$OUTER capture-pane -p -t outer:0.0 >"$DIR/screen" || exit 1
+sed -n 2p "$DIR/screen" | grep -q '^NEW02_#' || fail "row 2 not redrawn"
+sed -n 3p "$DIR/screen" | grep -q '^ROW03_x' || fail "row 3 overwritten"
+sed -n 6p "$DIR/screen" | grep -q '^NEW06_%' || fail "row 6 not redrawn"
+exit 0

regress/tty-keys.sh

@@ -9,14 +9,37 @@ $TMUX kill-server 2>/dev/null
 TMUX2="$TEST_TMUX -LtestB$$ -f/dev/null"
 $TMUX2 kill-server 2>/dev/null
 
-TMP=$(mktemp)
-trap "rm -f $TMP" 0 1 15
+TMP=$(mktemp) || exit 1
+prompt_pid=
+
+cleanup () {
+	if [ -n "$prompt_pid" ]; then
+		kill "$prompt_pid" 2>/dev/null
+		wait "$prompt_pid" 2>/dev/null
+	fi
+	$TMUX kill-server 2>/dev/null
+	$TMUX2 kill-server 2>/dev/null
+	rm -f "$TMP"
+}
+trap cleanup 0
+trap 'exit 1' 1 2 15
+
+fail () {
+	echo "[FAIL] $*" >&2
+	exit 1
+}
 
 $TMUX2 -f/dev/null new -d || exit 1
 $TMUX -f/dev/null new -d "$TMUX2 attach" || exit 1
-sleep 1
+i=0
+while [ -z "$($TMUX2 list-clients -F '#{client_name}')" ]; do
+	[ "$i" -lt 100 ] || fail "inner client did not attach"
+	sleep 0.05
+	i=$((i + 1))
+done
 
 exit_status=0
+assertion=0
 
 format_string () {
 	case $1 in
@@ -34,12 +57,33 @@ assert_key () {
 	expected_name=$2
 	format_string=$(format_string "$expected_name")
 
-	$TMUX2 command-prompt -k 'display-message -pl '"$format_string" > "$TMP" &
-	sleep 0.05
+	# Use a different prompt each time so a stale redraw cannot look ready.
+	assertion=$((assertion + 1))
+	prompt="tty-keys-$assertion:"
+	$TMUX2 command-prompt -k -p "$prompt" \
+	    'display-message -pl '"$format_string" > "$TMP" &
+	prompt_pid=$!
+	i=0
+	while ! $TMUX capture-pane -p | grep -Fq "$prompt"; do
+		kill -0 "$prompt_pid" 2>/dev/null || \
+		    fail "$keys -> $expected_name: prompt exited before becoming ready"
+		[ "$i" -lt 100 ] || \
+		    fail "$keys -> $expected_name: timed out waiting for prompt"
+		sleep 0.05
+		i=$((i + 1))
+	done
 
-	$TMUX send-keys $keys
+	$TMUX send-keys $keys || fail "could not send $keys"
 
-	wait
+	i=0
+	while kill -0 "$prompt_pid" 2>/dev/null; do
+		[ "$i" -lt 100 ] || \
+		    fail "$keys -> $expected_name: timed out waiting for key"
+		sleep 0.05
+		i=$((i + 1))
+	done
+	wait "$prompt_pid" || fail "$keys -> $expected_name: prompt failed"
+	prompt_pid=
 
 	keys=$(printf '%s' "$keys" | sed -e 's/Escape/\\\\033/g' | tr -d '[:space:]')
 	actual_name=$(tr -d '[:space:]' < "$TMP")
@@ -293,6 +337,16 @@ assert_key 'Escape [24@' 'C-S-F12'
 assert_key 'Escape [I' 'FocusIn'
 assert_key 'Escape [O' 'FocusOut'
 
+# Focus events do not leave the prefix table.
+$TMUX2 bind C-c set -g @focus-prefix yes
+$TMUX2 set -g focus-events on
+$TMUX send-keys C-b Escape '[O' Escape '[I' C-c
+sleep 0.05
+if [ "$($TMUX2 show -gv @focus-prefix)" != yes ]; then
+	echo "[FAIL] FocusIn and FocusOut left the prefix table"
+	exit_status=1
+fi
+
 # Paste keys
 assert_key 'Escape [200~' 'PasteStart'
 assert_key 'Escape [201~' 'PasteEnd'
@@ -355,7 +409,4 @@ assert_key 'Escape [32;2u' 'S-Space'
 assert_key 'Escape [9;5u' 'C-Tab'
 assert_key 'Escape [1;5Z' 'C-S-Tab'
 
-$TMUX kill-server 2>/dev/null
-$TMUX2 kill-server 2>/dev/null
-
 exit $exit_status

regress/tty-margins-scrollbar.sh

@@ -0,0 +1,93 @@
+#!/bin/sh
+
+# With left/right margins, a pane narrowed by a scrollbar can scroll without
+# retransmitting its existing rows. Both paths must produce the same screen.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lmarginsscrollbar-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lmarginsscrollbar-outer-$$ -f/dev/null"
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+cat >"$DIR/emitter.pl" <<'PERL'
+use strict;
+use warnings;
+$| = 1;
+print join("\r\n", map { "KEEP0$_" } 1 .. 6);
+while (!-e $ENV{TRIGGER}) {
+	select undef, undef, undef, 0.01;
+}
+print "\r\nNEWROW";
+sleep 100;
+PERL
+
+for margins in on off; do
+	$INNER new-session -d -s inner -x 40 -y 6 \
+	    "TRIGGER='$DIR/trigger-$margins' perl '$DIR/emitter.pl'" || exit 1
+	$INNER set -g status off || exit 1
+	$INNER set -g status-interval 0 || exit 1
+	$INNER set -g automatic-rename off || exit 1
+	$INNER set -g window-size manual || exit 1
+	$INNER set -g pane-scrollbars on || exit 1
+	if [ "$margins" = on ]; then
+		$INNER set -as terminal-features ',screen-256color:margins' || exit 1
+	fi
+
+	$OUTER new-session -d -s outer -x 40 -y 6 'sleep 100' || exit 1
+	$OUTER set -g status off || exit 1
+	$OUTER set -g window-size manual || exit 1
+	$OUTER set -g default-terminal screen-256color || exit 1
+	$OUTER respawn-pane -k -t outer:0.0 "$INNER attach -t inner" || exit 1
+	sleep 0.5
+	$OUTER pipe-pane -O -t outer:0.0 "cat >'$DIR/output-$margins'" || exit 1
+	$INNER refresh-client || exit 1
+	sleep 0.5
+	grep -aq KEEP02 "$DIR/output-$margins" || fail "initial rows not captured"
+	offset=$(wc -c <"$DIR/output-$margins")
+	: >"$DIR/trigger-$margins"
+	i=0
+	while [ "$i" -lt 50 ]; do
+		$OUTER capture-pane -p -t outer:0.0 >"$DIR/screen-$margins" || exit 1
+		grep -q NEWROW "$DIR/screen-$margins" && break
+		sleep 0.1
+		i=$((i + 1))
+	done
+	[ "$i" -lt 50 ] || fail "$margins: scroll did not reach the terminal"
+	sleep 0.2
+	tail -c +"$((offset + 1))" "$DIR/output-$margins" >"$DIR/scroll-$margins"
+	grep -aq NEWROW "$DIR/scroll-$margins" || fail "scroll output not captured"
+	if [ "$margins" = on ]; then
+		if grep -aq KEEP02 "$DIR/scroll-$margins"; then
+			fail "scroll with margins retransmitted an existing row"
+		fi
+	else
+		grep -aq KEEP02 "$DIR/scroll-$margins" ||
+		    fail "scroll without margins did not exercise the redraw fallback"
+	fi
+	printf 'KEEP02\nKEEP03\nKEEP04\nKEEP05\nKEEP06\nNEWROW\n' >"$DIR/expected"
+	cmp -s "$DIR/expected" "$DIR/screen-$margins" ||
+	    fail "$margins: terminal did not contain the expected scrolled rows"
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+done
+
+exit 0

regress/wait-for-client-lost.sh

@@ -0,0 +1,164 @@
+#!/bin/sh
+
+# A disconnected waiter must release both its wait and its command queue.
+PATH=/bin:/usr/bin
+TERM=screen
+export TERM
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+OUT=$(mktemp -d)
+TMUX="$TEST_TMUX -S$OUT/socket -f/dev/null"
+pids=
+
+cleanup()
+{
+	for pid in $pids; do
+		kill "$pid" 2>/dev/null || true
+	done
+	$TMUX kill-server 2>/dev/null || true
+	rm -rf "$OUT"
+}
+trap cleanup EXIT
+
+fail()
+{
+	echo "$*" >&2
+	exit 1
+}
+
+wait_list()
+{
+	expected=$1
+	shift
+	i=0
+	while [ $i -lt 100 ]; do
+		value=$($TMUX wait-for -l "$@") || fail "list waiters failed"
+		[ "$value" = "$expected" ] && return
+		i=$((i + 1))
+		sleep 0.05
+	done
+	fail "expected waiters '$expected', got '$value'"
+}
+
+wait_free()
+{
+	client_pid=$1
+	i=0
+	while [ $i -lt 100 ]; do
+		awk -v pid="$client_pid" '
+		    $4 == "IDENTIFY_CLIENTPID" && $5 == pid { address = $3 }
+		    address != "" && $2 == "free" && $3 == "client" &&
+		    $4 == address && $5 == "(0" { freed = 1 }
+		    END { exit !freed }
+		' "$OUT"/tmux-server-*.log && return
+		i=$((i + 1))
+		sleep 0.05
+	done
+	fail "client $client_pid was not freed"
+}
+
+cd "$OUT" || exit 1
+$TMUX -vv new-session -d -s test || fail "new-session failed"
+$TMUX set -g @continued 0 || fail "set option failed"
+
+for signal in TERM KILL; do
+	for kind in channel lock event; do
+		name="$kind-$signal"
+		case $kind in
+		channel) args="$name"; list_args="$name" ;;
+		lock)
+			$TMUX wait-for -L "$name" || fail "lock failed"
+			args="-L $name"; list_args="$name"
+			;;
+		event) args="-E @$name"; list_args="-E @$name" ;;
+		esac
+
+		$TMUX wait-for $args \; set -g @continued 1 &
+		dead=$!
+		pids="$dead"
+		wait_list "client-$dead" $list_args
+
+		$TMUX wait-for $args &
+		live=$!
+		pids="$dead $live"
+		wait_list "$(printf 'client-%s\nclient-%s' "$dead" "$live")" \
+		    $list_args
+
+		kill -"$signal" "$dead" || fail "kill failed"
+		wait "$dead" 2>/dev/null || true
+		pids="$live"
+		wait_list "client-$live" $list_args
+		wait_free "$dead"
+		[ "$($TMUX show -gqv @continued)" = 0 ] ||
+			fail "disconnected client's next command ran"
+
+		case $kind in
+		channel) $TMUX wait-for -S "$name" || fail "signal failed" ;;
+		lock) $TMUX wait-for -U "$name" || fail "unlock failed" ;;
+		event)
+			$TMUX wait-for -E -w "client-$live" "@$name" ||
+				fail "wake event waiter failed"
+			;;
+		esac
+		wait_list "" $list_args
+		wait_free "$live"
+		wait "$live" || fail "surviving waiter failed"
+		pids=
+		if [ "$kind" = lock ]; then
+			$TMUX wait-for -U "$name" || fail "final unlock failed"
+		fi
+	done
+done
+
+# Removing the last waiter must remove its otherwise unused channel, and must
+# not create a pending signal. Unrelated pending signals must be preserved.
+$TMUX wait-for -S saved || fail "save signal failed"
+$TMUX wait-for last &
+dead=$!
+pids="$dead"
+wait_list "client-$dead" last
+kill -KILL "$dead" || fail "kill last waiter failed"
+wait "$dead" 2>/dev/null || true
+pids=
+wait_list "" last
+wait_free "$dead"
+grep -F 'remove empty wait channel last' "$OUT"/tmux-server-*.log \
+    >/dev/null || fail "empty channel was not removed"
+
+$TMUX wait-for saved \; wait-for last &
+live=$!
+pids="$live"
+wait_list "client-$live" last
+$TMUX wait-for -S last || fail "signal last failed"
+wait_free "$live"
+wait "$live" || fail "pending signal was not preserved"
+pids=
+
+# Source-file leaves a cleanup callback behind the blocked command.
+printf 'wait-for sourced\nset -g @continued 1\n' >"$OUT/source.conf"
+$TMUX source-file "$OUT/source.conf" &
+dead=$!
+pids="$dead"
+wait_list "client-$dead" sourced
+kill -KILL "$dead" || fail "kill source-file waiter failed"
+wait "$dead" 2>/dev/null || true
+pids=
+wait_list "" sourced
+wait_free "$dead"
+[ "$($TMUX show -gqv @continued)" = 0 ] ||
+	fail "disconnected source-file client's next command ran"
+
+# Firing an event after cancellation must not call the removed event sink.
+$TMUX wait-for -E window-renamed &
+dead=$!
+pids="$dead"
+wait_list "client-$dead" -E window-renamed
+kill -KILL "$dead" || fail "kill event waiter failed"
+wait "$dead" 2>/dev/null || true
+pids=
+wait_list "" -E window-renamed
+wait_free "$dead"
+$TMUX rename-window -t test:0 renamed || fail "rename-window failed"
+$TMUX display-message -p '#{pid}' >/dev/null || fail "server exited"
+
+exit 0

regress/window-copy-scrollbar-drag-focus-style.sh

@@ -0,0 +1,123 @@
+#!/bin/sh
+
+# Dragging an inactive pane's scrollbar slider changes which pane is
+# active (window_copy_scroll(), window-copy.c). Every other place in the
+# codebase that changes the active pane pairs it with
+# window_redraw_active_switch() (or falls back to a full window redraw) so
+# the old/new active panes' window-active-style/window-style colours get
+# repainted - window_copy_scroll() was the one caller that did neither, so
+# a scrollbar-slider drag changed focus but left both panes' body colours
+# stale. This used to be masked by window_set_active_pane() itself doing
+# an unconditional full redraw on every active-pane change, until that was
+# narrowed to borders/status-only for the common case.
+#
+# This creates two tiled panes with clearly distinguishable
+# window-active-style/window-style backgrounds, puts the *inactive* one in
+# copy mode, drags its scrollbar slider, and checks - via an attached
+# client's own received bytes, since window-style is applied during
+# redraw composition rather than stored in the grid, so capture-pane
+# alone would not reflect it - that the newly active pane's marker text
+# immediately shows the active-style colour, not the stale one.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export PATH TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+
+DIR=$(mktemp -d) || exit 1
+INNER="$TEST_TMUX -Lsbfocus-inner-$$ -f/dev/null"
+OUTER="$TEST_TMUX -Lsbfocus-outer-$$ -f/dev/null"
+CAPTURE=$DIR/capture
+ESC=$(printf '\033')
+
+fail()
+{
+	echo "$*" >&2
+	[ -s "$CAPTURE" ] && cat -A "$CAPTURE" >&2
+	exit 1
+}
+
+cleanup()
+{
+	$OUTER kill-server 2>/dev/null
+	$INNER kill-server 2>/dev/null
+	rm -rf "$DIR"
+}
+trap cleanup 0 1 15
+
+get_mark_color()
+{
+	$OUTER capture-pane -e -p -t outer:0.0 >"$CAPTURE" 2>/dev/null || true
+	LC_ALL=C grep -a "MARK1" "$CAPTURE" |
+	    LC_ALL=C grep -aoE "${ESC}\[4[12]m" | tail -1
+}
+
+wait_mark_color()
+{
+	want=$1
+	i=0
+	while [ "$i" -lt 50 ]; do
+		[ "$(get_mark_color)" = "$want" ] && return 0
+		sleep 0.1
+		i=$((i + 1))
+	done
+	fail "MARK1's pane never showed the expected background (wanted '$want', got '$(get_mark_color)')"
+}
+
+mouse()
+{
+	sequence=$(printf '\033[<%s;%s;%s%s' "$1" "$2" "$3" "$4")
+	$OUTER send-keys -t outer:0.0 -l "$sequence" || exit 1
+	sleep 0.1
+}
+
+$INNER new-session -d -s inner -x 40 -y 10 'sleep 100' || exit 1
+$INNER set-option -g status off || exit 1
+$INNER set-option -g window-size manual || exit 1
+$INNER set-option -g mouse on || exit 1
+$INNER set-option -g pane-scrollbars on || exit 1
+$INNER setw pane-scrollbars-position right || exit 1
+$INNER setw pane-scrollbars-style 'width=1,pad=0' || exit 1
+$INNER set-option -g window-active-style 'bg=red' || exit 1
+$INNER set-option -g window-style 'bg=green' || exit 1
+$INNER split-window -h -t inner -d 'printf MARK1; sleep 100' || exit 1
+
+PANE1=$($INNER list-panes -t inner -F '#{pane_id}' | sed -n 2p)
+[ "$($INNER display-message -p -t "$PANE1" '#{pane_active}')" = 0 ] ||
+	fail "sanity: MARK1's pane is already active before the drag"
+
+# Put the inactive pane in copy mode without switching focus (copy-mode -t
+# targets a pane without making it active).
+$INNER copy-mode -t "$PANE1" || exit 1
+
+$OUTER new-session -d -s outer -x 40 -y 10 'sleep 100' || exit 1
+$OUTER set-option -g status off || exit 1
+$OUTER set-option -g window-size manual || exit 1
+$OUTER set-option -g default-terminal screen-256color || exit 1
+$OUTER respawn-pane -k -t outer:0.0 \
+    "$TEST_TMUX -Lsbfocus-inner-$$ -f/dev/null attach-session -t inner" ||
+    exit 1
+
+wait_mark_color "${ESC}[42m"
+
+XOFF=$($INNER display-message -p -t "$PANE1" '#{pane_left}')
+YOFF=$($INNER display-message -p -t "$PANE1" '#{pane_top}')
+SX=$($INNER display-message -p -t "$PANE1" '#{pane_width}')
+SBCOL=$((XOFF + SX + 1))
+SBROW=$((YOFF + 1))
+
+# With no scrollback beyond the pane's own content, the slider fills the
+# whole scrollbar track, so any point on it (here, its very first row) is
+# on the slider.
+mouse 0 "$SBCOL" "$SBROW" M
+mouse 32 "$SBCOL" "$((SBROW + 1))" M
+mouse 0 "$SBCOL" "$((SBROW + 1))" m
+
+[ "$($INNER display-message -p -t "$PANE1" '#{pane_active}')" = 1 ] ||
+	fail "sanity: dragging the scrollbar slider did not change focus"
+
+wait_mark_color "${ESC}[41m"
+
+exit 0

screen-redraw.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: screen-redraw.c,v 1.159 2026/09/09 08:31:42 nicm Exp $ */
+/* $OpenBSD: screen-redraw.c,v 1.161 2026/09/22 16:56:07 nicm Exp $ */
 
 /*
  * Copyright (c) 2026 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -33,7 +33,7 @@
  * this is done at various points, such as when a pane is moved or resized. The
  * scene only includes the part of the client used for the window: panes, pane
  * status lines, borders, scrollbars, and any area outside the window. The
- * client status line and overlay are not included.
+ * client status line is not included.
  *
  * A scene is made from spans. A span is a horizontal run of cells on one
  * visible line that can be drawn in the same way. Each span has a type, for
@@ -93,7 +93,6 @@ enum redraw_span_type {
 #define REDRAW_PANE_SCROLLBAR 0x20
 #define REDRAW_STATUS 0x40
 #define REDRAW_MENU 0x80
-#define REDRAW_OVERLAY 0x100
 
 /* Draw everything. */
 #define REDRAW_ALL 0x7fffffff
@@ -205,14 +204,36 @@ struct redraw_scene {
 	u_int			 oy;
 };
 
+/* A damaged rectangle in a window. */
+struct redraw_damage {
+	u_int				 x;
+	u_int				 y;
+	u_int				 sx;
+	u_int				 sy;
+
+	TAILQ_ENTRY(redraw_damage)	entry;
+};
+
+/*
+ * If there are more damage rectangles than this, they are collapsed into
+ * one.
+ */
+#define REDRAW_DAMAGE_MAX 16
+
 /* Cell for building the scene. */
 struct redraw_build_cell {
 	struct redraw_span_data	 data;
 };
-
 static struct redraw_build_cell	*redraw_cells;
 static size_t			 redraw_ncells;
 
+/*
+ * We can reuse the same pane status lines during one damage redraw, but when
+ * we enter a new one, the client or format variables may have changed, so we
+ * need to make them again. The generation is increased so this happens.
+ */
+static u_int	redraw_status_generation;
+
 /* Context for building the scene. */
 struct redraw_build_ctx {
 	struct client				*c;
@@ -264,8 +285,6 @@ redraw_flags_to_string(int flags)
 		strlcat(s, "scrollbar ", sizeof s);
 	if (flags & REDRAW_MENU)
 		strlcat(s, "menu ", sizeof s);
-	if (flags & REDRAW_OVERLAY)
-		strlcat(s, "overlay ", sizeof s);
 	if (REDRAW_IS_ALL(flags))
 		strlcat(s, "all ", sizeof s);
 	if (*s != '\0')
@@ -1057,6 +1076,13 @@ redraw_free_scene(struct redraw_scene *scene)
 	free(scene);
 }
 
+/* Does a client's cached scene show this window? */
+int
+redraw_client_has_window(struct client *c, struct window *w)
+{
+	return (c->redraw_scene != NULL && c->redraw_scene->w == w);
+}
+
 /* Mark a window's cached redraw scenes as out of date. */
 void
 redraw_invalidate_scene(struct window *w)
@@ -1064,6 +1090,104 @@ redraw_invalidate_scene(struct window *w)
 	w->redraw_scene_generation++;
 }
 
+/* Free all pending damage for a window. */
+void
+redraw_free_damage(struct window *w)
+{
+	struct redraw_damage	*rd, *rd1;
+
+	TAILQ_FOREACH_SAFE(rd, &w->damage, entry, rd1) {
+		TAILQ_REMOVE(&w->damage, rd, entry);
+		free(rd);
+	}
+	w->damage_count = 0;
+}
+
+/* Collapse all pending damage for a window into one rectangle. */
+static void
+redraw_collapse_damage(struct window *w)
+{
+	struct redraw_damage	*rd, *rd1, *first;
+	u_int			 x0, y0, x1, y1;
+
+	first = TAILQ_FIRST(&w->damage);
+	if (first == NULL)
+		return;
+	x0 = first->x;
+	y0 = first->y;
+	x1 = first->x + first->sx;
+	y1 = first->y + first->sy;
+
+	TAILQ_FOREACH_SAFE(rd, &w->damage, entry, rd1) {
+		if (rd->x < x0)
+			x0 = rd->x;
+		if (rd->y < y0)
+			y0 = rd->y;
+		if (rd->x + rd->sx > x1)
+			x1 = rd->x + rd->sx;
+		if (rd->y + rd->sy > y1)
+			y1 = rd->y + rd->sy;
+		if (rd != first) {
+			TAILQ_REMOVE(&w->damage, rd, entry);
+			free(rd);
+		}
+	}
+
+	first->x = x0;
+	first->y = y0;
+	first->sx = x1 - x0;
+	first->sy = y1 - y0;
+	w->damage_count = 1;
+}
+
+/* Record window damage, merging nearby rectangles and limiting the count. */
+void
+redraw_damage_window(struct window *w, u_int x, u_int y, u_int sx, u_int sy)
+{
+	struct redraw_damage	*rd;
+	u_int			 x0, y0, x1, y1, area, union_area;
+
+	if (x >= w->sx || y >= w->sy)
+		return;
+	if (x + sx > w->sx)
+		sx = w->sx - x;
+	if (y + sy > w->sy)
+		sy = w->sy - y;
+	if (sx == 0 || sy == 0)
+		return;
+
+	TAILQ_FOREACH(rd, &w->damage, entry) {
+		if (x > rd->x + rd->sx || rd->x > x + sx ||
+		    y > rd->y + rd->sy || rd->y > y + sy)
+			continue;
+
+		x0 = (x < rd->x) ? x : rd->x;
+		y0 = (y < rd->y) ? y : rd->y;
+		x1 = (x + sx > rd->x + rd->sx) ? x + sx : rd->x + rd->sx;
+		y1 = (y + sy > rd->y + rd->sy) ? y + sy : rd->y + rd->sy;
+
+		area = sx * sy + rd->sx * rd->sy;
+		union_area = (x1 - x0) * (y1 - y0);
+		if (union_area > 2 * area)
+			continue;
+
+		rd->x = x0;
+		rd->y = y0;
+		rd->sx = x1 - x0;
+		rd->sy = y1 - y0;
+		return;
+	}
+
+	rd = xcalloc(1, sizeof *rd);
+	rd->x = x;
+	rd->y = y;
+	rd->sx = sx;
+	rd->sy = sy;
+	TAILQ_INSERT_TAIL(&w->damage, rd, entry);
+	if (++w->damage_count > REDRAW_DAMAGE_MAX)
+		redraw_collapse_damage(w);
+}
+
 /* Mark all cached redraw scenes as out of date. */
 void
 redraw_invalidate_all_scenes(void)
@@ -1381,45 +1505,30 @@ static void
 redraw_draw_span(struct redraw_draw_ctx *dctx, struct redraw_span *span,
     u_int y)
 {
-	struct redraw_scene	*scene = dctx->scene;
 	struct redraw_span_data	*data = &span->data;
 	enum redraw_span_type	 type = data->type;
-	struct client		*c = scene->c;
-	struct tty		*tty = &c->tty;
-	struct visible_ranges	*r;
-	struct visible_range	*rr;
-	u_int			 i, x, n;
 
 	if (type == REDRAW_SPAN_STATUS && ~data->st.wp->flags & PANE_NEWSTATUS)
 		return;
 
-	r = tty_check_overlay_range(tty, span->x, y, span->width);
-	for (i = 0; i < r->used; i++) {
-		rr = &r->ranges[i];
-		if (rr->nx == 0)
-			continue;
-		x = rr->px;
-		n = rr->nx;
-
-		switch (span->data.type) {
-		case REDRAW_SPAN_PANE:
-			redraw_draw_pane_span(dctx, span, x, y, n);
-			break;
-		case REDRAW_SPAN_BORDER:
-		case REDRAW_SPAN_EMPTY:
-		case REDRAW_SPAN_OUTSIDE:
-			redraw_draw_border_span(dctx, span, x, y, n);
-			break;
-		case REDRAW_SPAN_STATUS:
-			redraw_draw_status_span(dctx, span, x, y, n);
-			break;
-		case REDRAW_SPAN_SCROLLBAR:
-			redraw_draw_scrollbar_span(dctx, span, x, y, n);
-			break;
-		case REDRAW_SPAN_MENU:
-			redraw_draw_menu_span(dctx, span, x, y, n);
-			break;
-		}
+	switch (span->data.type) {
+	case REDRAW_SPAN_PANE:
+		redraw_draw_pane_span(dctx, span, span->x, y, span->width);
+		break;
+	case REDRAW_SPAN_BORDER:
+	case REDRAW_SPAN_EMPTY:
+	case REDRAW_SPAN_OUTSIDE:
+		redraw_draw_border_span(dctx, span, span->x, y, span->width);
+		break;
+	case REDRAW_SPAN_STATUS:
+		redraw_draw_status_span(dctx, span, span->x, y, span->width);
+		break;
+	case REDRAW_SPAN_SCROLLBAR:
+		redraw_draw_scrollbar_span(dctx, span, span->x, y, span->width);
+		break;
+	case REDRAW_SPAN_MENU:
+		redraw_draw_menu_span(dctx, span, span->x, y, span->width);
+		break;
 	}
 }
 
@@ -1621,6 +1730,24 @@ redraw_set_draw_context(struct redraw_draw_ctx *dctx,
 		dctx->flags |= REDRAW_ISOLATES;
 }
 
+/* Build a pane prompt. */
+static void
+redraw_make_pane_prompt(struct window_pane *wp, struct screen *screen)
+{
+	struct screen_write_ctx	 ctx;
+	struct prompt_draw_data	 pdd;
+
+	screen_init(screen, wp->sx, 1, 0);
+	screen_write_start(&ctx, screen);
+	pdd.ctx = &ctx;
+	pdd.cursor_x = &wp->prompt_cx;
+	pdd.area_x = 0;
+	pdd.area_width = wp->sx;
+	pdd.prompt_line = 0;
+	prompt_draw(wp->prompt, &pdd);
+	screen_write_stop(&ctx);
+}
+
 /* Draw a pane's prompt over its content. */
 static void
 redraw_draw_pane_prompt(struct redraw_draw_ctx *dctx, struct window_pane *wp)
@@ -1629,8 +1756,6 @@ redraw_draw_pane_prompt(struct redraw_draw_ctx *dctx, struct window_pane *wp)
 	struct client		*c = scene->c;
 	struct tty		*tty = &c->tty;
 	struct screen		 screen;
-	struct screen_write_ctx	 ctx;
-	struct prompt_draw_data	 pdd;
 	int			 ox = scene->ox, oy = scene->oy;
 	int			 sx = scene->sx, sy = scene->sy;
 	int			 line, cy, px, offset, width, wy;
@@ -1663,17 +1788,8 @@ redraw_draw_pane_prompt(struct redraw_draw_ctx *dctx, struct window_pane *wp)
 	if (px + width > sx)
 		width = sx - px;
 
-	screen_init(&screen, wp->sx, 1, 0);
-	screen_write_start(&ctx, &screen);
-	pdd.ctx = &ctx;
-	pdd.cursor_x = &wp->prompt_cx;
-	pdd.area_x = 0;
-	pdd.area_width = wp->sx;
-	pdd.prompt_line = 0;
-	prompt_draw(wp->prompt, &pdd);
-	screen_write_stop(&ctx);
-
-	tty_draw_line(tty, &screen, 0, offset, width, px, cy, NULL);
+	redraw_make_pane_prompt(wp, &screen);
+	tty_draw_line(tty, &screen, offset, 0, width, px, cy, NULL);
 	screen_free(&screen);
 }
 
@@ -1688,10 +1804,8 @@ redraw_draw(struct client *c, struct window_pane *wp, int flags)
 	struct screen		*sl;
 	struct redraw_scene	*scene;
 	struct window_pane	*loop;
-	u_int			 width, i, y, lines, j;
+	u_int			 width, i, y, lines;
 	struct redraw_span	*first;
-	struct visible_ranges	*r;
-	struct visible_range	*rr;
 	int			 redraw;
 
 	if (c->flags & CLIENT_SUSPENDED)
@@ -1704,7 +1818,9 @@ redraw_draw(struct client *c, struct window_pane *wp, int flags)
 			redraw = status_prompt_redraw(c);
 		else
 			redraw = status_redraw(c);
-		if (!redraw && !REDRAW_IS_ALL(flags)) {
+		if (!redraw &&
+		    (~c->flags & CLIENT_REDRAWSTATUSALWAYS) &&
+		    !REDRAW_IS_ALL(flags)) {
 			flags &= ~REDRAW_STATUS;
 			if (flags == 0)
 				return;
@@ -1799,19 +1915,9 @@ redraw_draw(struct client *c, struct window_pane *wp, int flags)
 		else
 			y = c->tty.sy - lines;
 		sl = c->status.active;
-		for (i = 0; i < lines; i++) {
-			r = tty_check_overlay_range(tty, 0, y + i, tty->sx);
-			for (j = 0; j < r->used; j++) {
-				rr = &r->ranges[j];
-				if (rr->nx == 0)
-					continue;
-				tty_draw_line(tty, sl, rr->px, i, rr->nx,
-				    rr->px, y + i, NULL);
-			}
-		}
+		for (i = 0; i < lines; i++)
+			tty_draw_line(tty, sl, 0, i, tty->sx, 0, y + i, NULL);
 	}
-	if (c->overlay_draw != NULL && (flags & REDRAW_OVERLAY))
-		c->overlay_draw(c, c->overlay_data);
 
 	tty_reset(tty);
 
@@ -1867,18 +1973,13 @@ redraw_screen(struct client *c)
 {
 	int	flags = 0;
 
-	if (c->flags & CLIENT_REDRAWWINDOW) {
-		if (c->flags & CLIENT_REDRAWOVERLAY)
-			redraw_draw(c, NULL, REDRAW_ALL);
-		else
-			redraw_draw(c, NULL, REDRAW_ALL & ~REDRAW_OVERLAY);
-	} else {
+	if (c->flags & CLIENT_REDRAWWINDOW)
+		redraw_draw(c, NULL, REDRAW_ALL);
+	else {
 		if (c->flags & CLIENT_REDRAWBORDERS)
 			flags |= (REDRAW_PANE_BORDER|REDRAW_PANE_STATUS);
-		if (c->flags & CLIENT_REDRAWSTATUS)
+		if (c->flags & (CLIENT_REDRAWSTATUS|CLIENT_REDRAWSTATUSALWAYS))
 			flags |= (REDRAW_STATUS|REDRAW_PANE_STATUS);
-		if (c->flags & CLIENT_REDRAWOVERLAY)
-			flags |= REDRAW_OVERLAY;
 		if (c->flags & CLIENT_REDRAWMENU)
 			flags |= REDRAW_MENU;
 		if (c->session->curw->window->menu != NULL)
@@ -1903,3 +2004,138 @@ redraw_pane_scrollbar(struct client *c, struct window_pane *wp)
 {
 	redraw_draw(c, wp, REDRAW_PANE_SCROLLBAR);
 }
+
+/* Rebuild damaged pane status. */
+static void
+redraw_damage_refresh_status(struct redraw_draw_ctx *dctx,
+    struct window_pane *wp)
+{
+	struct redraw_span	*first;
+	u_int			 g = wp->status_generation, width;
+
+	if ((wp->flags & PANE_NEWSTATUS) && g == redraw_status_generation)
+		return;
+	width = redraw_pane_status_width(dctx, wp, &first);
+	if (width != 0) {
+		window_make_pane_status(wp, dctx->scene->c, width, first);
+		wp->flags |= PANE_NEWSTATUS;
+		wp->status_generation = redraw_status_generation;
+	}
+}
+
+/* Draw a pane's prompt over a damaged span. */
+static void
+redraw_damage_draw_pane_prompt(struct redraw_draw_ctx *dctx,
+    struct redraw_span *span, u_int y)
+{
+	struct redraw_scene	*scene = dctx->scene;
+	struct window_pane	*wp = span->data.p.wp;
+	struct tty		*tty = &scene->c->tty;
+	struct screen		 screen;
+	u_int			 px = span->data.p.px, width, prompt_y;
+
+	if (wp->prompt == NULL || wp->sx == 0 || wp->sy == 0)
+		return;
+	if (dctx->flags & REDRAW_STATUS_TOP)
+		prompt_y = 0;
+	else
+		prompt_y = wp->sy - 1;
+	if (span->data.p.py != prompt_y)
+		return;
+	redraw_make_pane_prompt(wp, &screen);
+	if (px < screen_size_x(&screen)) {
+		width = span->width;
+		if (width > screen_size_x(&screen) - px)
+			width = screen_size_x(&screen) - px;
+		tty_draw_line(tty, &screen, px, 0, width, span->x, y, NULL);
+	}
+	screen_free(&screen);
+}
+
+/* Draw the spans intersecting a damaged rectangle. */
+static void
+redraw_draw_damage_rectangle(struct redraw_draw_ctx *dctx, u_int x, u_int y,
+    u_int sx, u_int sy)
+{
+	struct redraw_scene	*scene = dctx->scene;
+	struct redraw_line	*line;
+	struct redraw_spans	*spans;
+	struct redraw_span	*span;
+	u_int			 cy, yy, type;
+
+	if (x >= scene->sx || y >= scene->sy)
+		return;
+	if (x + sx > scene->sx)
+		sx = scene->sx - x;
+	if (y + sy > scene->sy)
+		sy = scene->sy - y;
+	if (sx == 0 || sy == 0)
+		return;
+
+	for (yy = y; yy < y + sy; yy++) {
+		line = &scene->lines[yy];
+		if (dctx->flags & REDRAW_STATUS_TOP)
+			cy = dctx->status_lines + yy;
+		else
+			cy = yy;
+		for (type = 0; type < REDRAW_SPAN_TYPES; type++) {
+			spans = &line->spans[type];
+			TAILQ_FOREACH(span, spans, entry) {
+				if (span->x >= x + sx)
+					continue;
+				if (span->x + span->width <= x)
+					continue;
+				if (type == REDRAW_SPAN_STATUS) {
+					redraw_damage_refresh_status(dctx,
+					    span->data.st.wp);
+				}
+				redraw_draw_span(dctx, span, cy);
+				if (type == REDRAW_SPAN_PANE) {
+					redraw_damage_draw_pane_prompt(dctx,
+					    span, cy);
+				}
+			}
+		}
+	}
+}
+
+/* Draw pending window damage on this client. */
+void
+redraw_client_damage(struct client *c)
+{
+	struct window		*w = c->session->curw->window;
+	struct window_pane	*wp;
+	struct redraw_scene	*scene;
+	struct redraw_draw_ctx	 dctx;
+	struct redraw_damage	*rd;
+	u_int			 ox, oy, sx, sy, x0, y0, x1, y1;
+
+	if (TAILQ_EMPTY(&w->damage))
+		return;
+	redraw_status_generation++;
+
+	scene = redraw_get_scene(c);
+	if (scene == NULL)
+		return;
+	redraw_set_draw_context(&dctx, scene);
+	redraw_get_window_offset(c, &ox, &oy, &sx, &sy);
+
+	TAILQ_FOREACH(wp, &w->panes, entry) {
+		wp->border_gc_set = 0;
+		wp->active_border_gc_set = 0;
+	}
+
+	tty_sync_start(&c->tty);
+	tty_update_mode(&c->tty, c->tty.mode & ~CURSOR_MODES, NULL);
+
+	TAILQ_FOREACH(rd, &w->damage, entry) {
+		x0 = (rd->x > ox) ? rd->x : ox;
+		y0 = (rd->y > oy) ? rd->y : oy;
+		x1 = (rd->x + rd->sx < ox + sx) ? rd->x + rd->sx : ox + sx;
+		y1 = (rd->y + rd->sy < oy + sy) ? rd->y + rd->sy : oy + sy;
+		if (x0 < x1 && y0 < y1) {
+			redraw_draw_damage_rectangle(&dctx, x0 - ox, y0 - oy,
+			    x1 - x0, y1 - y0);
+		}
+	}
+}

screen-write.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: screen-write.c,v 1.290 2026/08/24 15:05:26 nicm Exp $ */
+/* $OpenBSD: screen-write.c,v 1.292 2026/09/21 12:14:32 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -120,14 +120,26 @@ screen_write_set_cursor(struct screen_write_ctx *ctx, int cx, int cy)
 		evtimer_add(&w->offset_timer, &tv);
 }
 
-/* Do a full redraw. */
+/* Redraw lines. */
 static void
-screen_write_redraw_cb(const struct tty_ctx *ttyctx)
+screen_write_redraw_cb(const struct tty_ctx *ttyctx, u_int py, u_int ny)
 {
 	struct window_pane	*wp = ttyctx->arg;
+	int			 x0, y0, x1, y1;
 
-	if (wp != NULL)
-		wp->flags |= PANE_REDRAW;
+	if (wp == NULL)
+		return;
+
+	x0 = wp->xoff;
+	y0 = wp->yoff + (int)py;
+	x1 = x0 + (int)wp->sx;
+	y1 = y0 + (int)ny;
+	if (x0 < 0)
+		x0 = 0;
+	if (y0 < 0)
+		y0 = 0;
+	if (x1 > x0 && y1 > y0)
+		redraw_damage_window(wp->window, x0, y0, x1 - x0, y1 - y0);
 }
 
 /* Update context for client. */
@@ -305,21 +317,16 @@ screen_write_initctx(struct screen_write_ctx *ctx, struct tty_ctx *ttyctx,
 
 	if (~ctx->flags & SCREEN_WRITE_SYNC) {
 		/*
-		 * For the active pane showing its base screen or for an
-		 * overlay (no pane), only use synchronized updates if
-		 * requested (commands that move the cursor); for other panes
-		 * or a pane in a mode, always use it, since the cursor will
-		 * have to move.
+		 * For the active pane showing its base screen, only use
+		 * synchronized updates if requested (commands that move the
+		 * cursor); for other panes or a pane in a mode, always use it,
+		 * since the cursor will have to move.
 		 */
 		if (ctx->wp != NULL && (ctx->wp != ctx->wp->window->active ||
 		    ctx->wp->screen != &ctx->wp->base))
 			ttyctx->flags |= TTY_CTX_SYNC;
-		else {
-			if (ctx->wp == NULL)
-				ttyctx->flags |= TTY_CTX_OVERLAY_SYNC;
-			if (is_sync)
-				ttyctx->flags |= TTY_CTX_SYNC;
-		}
+		else if (is_sync)
+			ttyctx->flags |= TTY_CTX_SYNC;
 		tty_write(tty_cmd_syncstart, ttyctx);
 		ctx->flags |= SCREEN_WRITE_SYNC;
 	}
@@ -714,7 +721,7 @@ screen_write_fast_copy(struct screen_write_ctx *ctx, struct screen *src,
 			if (!window_position_is_visible(r, xoff + s->cx))
 				break;
 			ttyctx.cell = &gc;
-			ttyctx.flags &= (TTY_CTX_OVERLAY_SYNC|TTY_CTX_SYNC);
+			ttyctx.flags &= TTY_CTX_SYNC;
 			tty_write(tty_cmd_cell, &ttyctx);
 			ttyctx.ocx++;
 
@@ -838,34 +845,39 @@ screen_write_menu(struct screen_write_ctx *ctx, struct menu *menu, int choice,
 	struct screen		*s = ctx->s;
 	struct grid_cell	 default_gc;
 	const struct grid_cell	*gc = &default_gc;
-	u_int			 cx, cy, i, j, width = menu->width;
+	u_int			 border, cx = s->cx, cy = s->cy, i, j, width;
 	const char		*name;
 
-	cx = s->cx;
-	cy = s->cy;
-
 	memcpy(&default_gc, menu_gc, sizeof default_gc);
 
-	screen_write_box(ctx, menu->width + 4, menu->count + 2, lines,
-	    border_gc, menu->title);
+	if (lines == BOX_LINES_NONE) {
+		border = 0;
+		width = menu->item_width;
+	} else {
+		border = 1;
+		width = menu->width;
+		screen_write_box(ctx, width + 4, menu->count + 2, lines,
+		    border_gc, menu->title);
+	}
 
 	for (i = 0; i < menu->count; i++) {
 		name = menu->items[i].name;
 		if (name == NULL) {
-			screen_write_cursormove(ctx, cx, cy + 1 + i, 0);
-			screen_write_hline(ctx, width + 4, 1, 1, lines,
-			    border_gc);
+			screen_write_cursormove(ctx, cx, cy + border + i, 0);
+			screen_write_hline(ctx, width + 2 + (2 * border), 1, 1,
+			    lines, border_gc);
 			continue;
 		}
 
 		if (choice >= 0 && i == (u_int)choice && *name != '-')
 			gc = choice_gc;
 
-		screen_write_cursormove(ctx, cx + 1, cy + 1 + i, 0);
+		screen_write_cursormove(ctx, cx + border, cy + border + i, 0);
 		for (j = 0; j < width + 2; j++)
 			screen_write_putc(ctx, gc, ' ');
 
-		screen_write_cursormove(ctx, cx + 2, cy + 1 + i, 0);
+		screen_write_cursormove(ctx, cx + border + 1, cy + border + i,
+		    0);
 		if (*name == '-') {
 			default_gc.attr |= GRID_ATTR_DIM;
 			format_draw(ctx, gc, width, name + 1, NULL, 0);
@@ -2155,7 +2167,7 @@ screen_write_fullredraw(struct screen_write_ctx *ctx)
 
 	screen_write_initctx(ctx, &ttyctx, 1, 0);
 	if (ttyctx.redraw_cb != NULL)
-		ttyctx.redraw_cb(&ttyctx);
+		ttyctx.redraw_cb(&ttyctx, 0, ttyctx.sy);
 }
 
 /* Trim collected items. */
@@ -3175,7 +3187,7 @@ screen_write_alternateon(struct screen_write_ctx *ctx, struct grid_cell *gc,
 
 	screen_write_initctx(ctx, &ttyctx, 1, 0);
 	if (ttyctx.redraw_cb != NULL)
-		ttyctx.redraw_cb(&ttyctx);
+		ttyctx.redraw_cb(&ttyctx, 0, ttyctx.sy);
 }
 
 /* Turn alternate screen off. */
@@ -3200,5 +3212,5 @@ screen_write_alternateoff(struct screen_write_ctx *ctx, struct grid_cell *gc,
 
 	screen_write_initctx(ctx, &ttyctx, 1, 0);
 	if (ttyctx.redraw_cb != NULL)
-		ttyctx.redraw_cb(&ttyctx);
+		ttyctx.redraw_cb(&ttyctx, 0, ttyctx.sy);
 }

server-client.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: server-client.c,v 1.511 2026/09/08 10:20:08 nicm Exp $ */
+/* $OpenBSD: server-client.c,v 1.514 2026/09/22 06:46:50 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -67,77 +67,6 @@ server_client_how_many(void)
 	return (n);
 }
 
-/* Overlay timer callback. */
-static void
-server_client_overlay_timer(__unused int fd, __unused short events, void *data)
-{
-	server_client_clear_overlay(data);
-}
-
-/* Set an overlay on client. */
-void
-server_client_set_overlay(struct client *c, u_int delay,
-    overlay_check_cb checkcb, overlay_mode_cb modecb,
-    overlay_draw_cb drawcb, overlay_key_cb keycb, overlay_free_cb freecb,
-    overlay_resize_cb resizecb, void *data)
-{
-	struct timeval	tv;
-
-	if (c->overlay_draw != NULL)
-		server_client_clear_overlay(c);
-
-	tv.tv_sec = delay / 1000;
-	tv.tv_usec = (delay % 1000) * 1000L;
-
-	if (event_initialized(&c->overlay_timer))
-		evtimer_del(&c->overlay_timer);
-	evtimer_set(&c->overlay_timer, server_client_overlay_timer, c);
-	if (delay != 0)
-		evtimer_add(&c->overlay_timer, &tv);
-
-	c->overlay_check = checkcb;
-	c->overlay_mode = modecb;
-	c->overlay_draw = drawcb;
-	c->overlay_key = keycb;
-	c->overlay_free = freecb;
-	c->overlay_resize = resizecb;
-	c->overlay_data = data;
-
-	if (c->overlay_check == NULL)
-		c->tty.flags |= TTY_FREEZE;
-	if (c->overlay_mode == NULL)
-		c->tty.flags |= TTY_NOCURSOR;
-	window_update_focus(c->session->curw->window);
-	server_redraw_client(c);
-}
-
-/* Clear overlay mode on client. */
-void
-server_client_clear_overlay(struct client *c)
-{
-	if (c->overlay_draw == NULL)
-		return;
-
-	if (event_initialized(&c->overlay_timer))
-		evtimer_del(&c->overlay_timer);
-
-	if (c->overlay_free != NULL)
-		c->overlay_free(c, c->overlay_data);
-
-	c->overlay_check = NULL;
-	c->overlay_mode = NULL;
-	c->overlay_draw = NULL;
-	c->overlay_key = NULL;
-	c->overlay_free = NULL;
-	c->overlay_resize = NULL;
-	c->overlay_data = NULL;
-
-	c->tty.flags &= ~(TTY_FREEZE|TTY_NOCURSOR);
-	if (c->session != NULL)
-		window_update_focus(c->session->curw->window);
-	server_redraw_client(c);
-}
-
 /* Are these ranges empty? That is, nothing is visible. */
 int
 server_client_ranges_is_empty(struct visible_ranges *r)
@@ -161,52 +90,6 @@ server_client_ensure_ranges(struct visible_ranges *r, u_int n)
 	r->size = n;
 }
 
-/*
- * Given overlay position and dimensions, return parts of the input range which
- * are visible.
- */
-void
-server_client_overlay_range(u_int x, u_int y, u_int sx, u_int sy, u_int px,
-    u_int py, u_int nx, struct visible_ranges *r)
-{
-	u_int	ox, onx;
-
-	/* Trivial case of no overlap in the y direction. */
-	if (py < y || py > y + sy - 1) {
-		server_client_ensure_ranges(r, 1);
-		r->ranges[0].px = px;
-		r->ranges[0].nx = nx;
-		r->used = 1;
-		return;
-	}
-	server_client_ensure_ranges(r, 2);
-
-	/* Visible bit to the left of the popup. */
-	if (px < x) {
-		r->ranges[0].px = px;
-		r->ranges[0].nx = x - px;
-		if (r->ranges[0].nx > nx)
-			r->ranges[0].nx = nx;
-	} else {
-		r->ranges[0].px = 0;
-		r->ranges[0].nx = 0;
-	}
-
-	/* Visible bit to the right of the popup. */
-	ox = x + sx;
-	if (px > ox)
-		ox = px;
-	onx = px + nx;
-	if (onx > ox) {
-		r->ranges[1].px = ox;
-		r->ranges[1].nx = onx - ox;
-	} else {
-		r->ranges[1].px = 0;
-		r->ranges[1].nx = 0;
-	}
-	r->used = 2;
-}
-
 /* Check if this client is inside this server. */
 int
 server_client_check_nested(struct client *c)
@@ -473,7 +356,13 @@ server_client_set_session(struct client *c, struct session *s)
 		tty_update_client_offset(c);
 		status_timer_start(c);
 		server_client_fire_session_changed(c, old);
-		server_redraw_client(c);
+
+		/*
+		 * Redraw if the session or displayed window changed. Use the
+		 * cached scene because the session's current window is already set.
+		 */
+		if (old != s || !redraw_client_has_window(c, s->curw->window))
+			server_redraw_client(c);
 	}
 
 	server_check_unattached();
@@ -490,7 +379,6 @@ server_client_lost(struct client *c)
 		cfg_client = NULL;
 	c->flags |= CLIENT_DEAD;
 
-	server_client_clear_overlay(c);
 	status_prompt_clear(c);
 	status_message_clear(c);
 
@@ -502,6 +390,9 @@ server_client_lost(struct client *c)
 	TAILQ_REMOVE(&clients, c, entry);
 	log_debug("lost client %p", c);
 
+	cmd_wait_for_client_lost(c);
+	cmdq_next(c);
+
 	if (c->flags & CLIENT_ATTACHED) {
 		server_client_attached_lost(c);
 		events_fire_client("client-detached", c);
@@ -1391,15 +1282,19 @@ server_client_repeat_time(struct client *c, struct key_binding *bd)
 	return (repeat);
 }
 
-/* Handle a key press on a dead pane waiting for a key. */
+/* Handle a key press which closes a dead pane. */
 static int
 server_client_handle_dead_key(struct window_pane *wp, key_code key)
 {
+	int	remain_on_exit;
+
 	if (wp == NULL ||
 	    (~wp->flags & PANE_EXITED) ||
 	    KEYC_IS_MOUSE(key) ||
-	    KEYC_IS_PASTE(key) ||
-	    options_get_number(wp->options, "remain-on-exit") != 3)
+	    KEYC_IS_PASTE(key))
+		return (0);
+	remain_on_exit = options_get_number(wp->options, "remain-on-exit");
+	if (remain_on_exit != 3 && remain_on_exit != 4)
 		return (0);
 	options_set_number(wp->options, "remain-on-exit", 0);
 	server_destroy_pane(wp, 0);
@@ -1460,10 +1355,11 @@ server_client_key_callback(struct cmdq_item *item, void *data)
 		m->key = key;
 
 		/*
-		 * Mouse drag is in progress, so fire the callback (now that
-		 * the mouse event is valid).
+		 * Synchronize direct drag output with the later damage redraw
+		 * before invoking the drag callback.
 		 */
 		if ((key & KEYC_MASK_KEY) == KEYC_DRAGGING) {
+			tty_sync_start(&c->tty);
 			c->tty.mouse_drag_update(c, m);
 			goto out;
 		}
@@ -1742,10 +1638,6 @@ server_client_handle_key0(struct client *c, struct key_event *event,
 	if (s == NULL || (c->flags & CLIENT_UNATTACHEDFLAGS))
 		return (0);
 
-	/*
-	 * Handle theme reporting keys before overlays so they work even when a
-	 * popup is open.
-	 */
 	if (event->key == KEYC_REPORT_LIGHT_THEME) {
 		server_client_report_theme(c, THEME_LIGHT);
 		return (0);
@@ -1756,9 +1648,9 @@ server_client_handle_key0(struct client *c, struct key_event *event,
 	}
 
 	/*
-	 * Key presses in overlay mode, for panes capturing all keys and in the
-	 * command prompt are a special case. The queue might be blocked so they
-	 * need to be processed immediately rather than queued.
+	 * Dead panes waiting for a key, modal cancel keys, panes capturing all keys
+	 * and the command prompt are special cases. The queue might be blocked so
+	 * they need to be processed immediately rather than queued.
 	 */
 	if (~c->flags & CLIENT_READONLY) {
 		if (c->message_string != NULL) {
@@ -1767,25 +1659,20 @@ server_client_handle_key0(struct client *c, struct key_event *event,
 			status_message_clear(c);
 		}
 
-		if (c->overlay_key != NULL) {
-			switch (c->overlay_key(c, c->overlay_data, event)) {
-			case 0:
-				return (0);
-			case 1:
-				server_client_clear_overlay(c);
-				return (0);
-			}
-		}
-
-		server_client_clear_overlay(c);
-
 		wp = s->curw->window->active;
+		if (server_client_handle_dead_key(wp, event->key))
+			return (0);
+		if (wp != NULL &&
+		    wp == wp->window->modal &&
+		    (wp->flags & PANE_CLOSEONCANCEL) &&
+		    (event->key == '\033' || event->key == ('c'|KEYC_CTRL))) {
+			server_kill_pane(wp);
+			return (0);
+		}
 		if (wp != NULL &&
 		    (wp->flags & PANE_CAPTUREALLKEYS) &&
 		    TAILQ_EMPTY(&wp->modes) &&
 		    !KEYC_IS_MOUSE(event->key)) {
-			if (server_client_handle_dead_key(wp, event->key))
-				return (0);
 			if (~wp->flags & PANE_EXITED) {
 				window_pane_key(wp, c, s, s->curw, event->key,
 				    &event->m);
@@ -1899,8 +1786,8 @@ server_client_loop(void)
 	}
 
 	/*
-	 * Any windows will have been redrawn as part of clients, so clear
-	 * their flags now.
+	 * Clear window redraw state after processing all clients. Deferred
+	 * redraws are preserved in client flags.
 	 */
 	RB_FOREACH(w, windows, &windows) {
 		TAILQ_FOREACH(wp, &w->panes, entry) {
@@ -1911,6 +1798,8 @@ server_client_loop(void)
 			wp->flags &= ~(PANE_REDRAW|PANE_REDRAWSCROLLBAR|
 			    PANE_ACTIVITY);
 		}
+		redraw_free_damage(w);
+
 		check_window_name(w);
 	}
 
@@ -2166,11 +2055,8 @@ server_client_reset_state(struct client *c)
 	flags = (tty->flags & TTY_BLOCK);
 	tty->flags &= ~TTY_BLOCK;
 
-	/* Get mode from overlay if any, else from screen. */
-	if (c->overlay_draw != NULL) {
-		if (c->overlay_mode != NULL)
-			s = c->overlay_mode(c, c->overlay_data, &cx, &cy);
-	} else if (w->menu != NULL) {
+	/* Get mode from the menu if any, else from the screen. */
+	if (w->menu != NULL) {
 		menu_get_cursor(w->menu, &cx, &cy);
 		s = menu_screen(w->menu);
 	} else if (wp != NULL && c->prompt == NULL)
@@ -2192,7 +2078,7 @@ server_client_reset_state(struct client *c)
 	if (c->prompt != NULL) {
 		prompt = 1;
 		status_prompt_cursor(c, &cx, &cy);
-	} else if (wp != NULL && c->overlay_draw == NULL) {
+	} else if (wp != NULL) {
 		if (w->menu != NULL) {
 			tty_window_offset(tty, &ox, &oy, &sx, &sy);
 			if (cx < ox || cx >= ox + sx ||
@@ -2247,7 +2133,7 @@ server_client_reset_state(struct client *c)
 			if (!cursor)
 				mode &= ~MODE_CURSOR;
 		}
-	} else if (c->overlay_mode == NULL || s == NULL)
+	} else if (s == NULL)
 		mode &= ~MODE_CURSOR;
 	if (~pane_mode & MODE_SYNC) {
 		log_debug("%s: cursor to %u,%u", __func__, cx, cy);
@@ -2264,7 +2150,7 @@ server_client_reset_state(struct client *c)
 	 * movement events.
 	 */
 	if (options_get_number(oo, "mouse")) {
-		if (c->overlay_draw == NULL && w->menu == NULL) {
+		if (w->menu == NULL) {
 			mode &= ~ALL_MOUSE_MODES;
 			TAILQ_FOREACH(loop, &w->panes, entry) {
 				if (loop->screen->mode & MODE_MOUSE_ALL)
@@ -2280,7 +2166,7 @@ server_client_reset_state(struct client *c)
 	}
 
 	/* Clear bracketed paste mode if at the prompt. */
-	if (c->overlay_draw == NULL && prompt)
+	if (prompt)
 		mode &= ~MODE_BRACKETPASTE;
 
 	/* Set the terminal mode and reset attributes. */
@@ -2459,6 +2345,8 @@ server_client_any_pane_redraw(struct client *c)
 
 	if (c->flags & CLIENT_REDRAWWINDOW)
 		return (1);
+	if (!TAILQ_EMPTY(&w->damage))
+		return (1);
 	TAILQ_FOREACH(wp, &w->panes, entry) {
 		if (wp->flags & (PANE_REDRAW|PANE_REDRAWSCROLLBAR))
 			return (1);
@@ -2475,6 +2363,7 @@ server_client_check_redraw(struct client *c)
 	struct window		*w = s->curw->window;
 	struct window_pane	*wp;
 	int			 needed, tflags, mode = tty->mode;
+	int			 damaged = !TAILQ_EMPTY(&w->damage);
 	struct timeval		 tv = { .tv_usec = 1000 };
 	static struct event	 ev;
 	size_t			 n;
@@ -2482,11 +2371,10 @@ server_client_check_redraw(struct client *c)
 	if (c->flags & (CLIENT_CONTROL|CLIENT_SUSPENDED))
 		return;
 	if (c->flags & CLIENT_ALLREDRAWFLAGS) {
-		log_debug("%s: redraw%s%s%s%s%s", c->name,
+		log_debug("%s: redraw%s%s%s%s", c->name,
 		    (c->flags & CLIENT_REDRAWWINDOW) ? " window" : "",
 		    (c->flags & CLIENT_REDRAWSTATUS) ? " status" : "",
 		    (c->flags & CLIENT_REDRAWBORDERS) ? " borders" : "",
-		    (c->flags & CLIENT_REDRAWOVERLAY) ? " overlay" : "",
 		    (c->flags & CLIENT_REDRAWMENU) ? " menu" : "");
 	}
 
@@ -2501,12 +2389,12 @@ server_client_check_redraw(struct client *c)
 		return;
 	}
 
-	/*
-	 * If there is outstanding data, defer the redraw until it has been
-	 * consumed. We can just add a timer to get out of the event loop and
-	 * end up back here.
-	 */
+	/* Ignore output queued within the current synchronized frame. */
 	n = EVBUFFER_LENGTH(tty->out);
+	if ((tty->flags & TTY_SYNCING) && n > tty->sync_offset)
+		n = tty->sync_offset;
+
+	/* Defer until output drains, preserving damage in client flags. */
 	if (n != 0 || (tty->flags & TTY_BLOCK)) {
 		if (n != 0)
 			log_debug("%s: redraw deferred (%zu left)", c->name, n);
@@ -2518,6 +2406,10 @@ server_client_check_redraw(struct client *c)
 			log_debug("redraw timer started");
 			evtimer_add(&ev, &tv);
 		}
+		if (damaged) {
+			c->flags |= CLIENT_REDRAWWINDOW;
+			return;
+		}
 		TAILQ_FOREACH(wp, &w->panes, entry) {
 			if (wp->flags & PANE_REDRAW) {
 				c->flags |= CLIENT_REDRAWWINDOW;
@@ -2551,6 +2443,10 @@ server_client_check_redraw(struct client *c)
 				redraw_pane_scrollbar(c, wp);
 			}
 		}
+
+		/* Draw damage here if no client redraw flags will handle it. */
+		if (damaged && (c->flags & CLIENT_ALLREDRAWFLAGS) == 0)
+			redraw_client_damage(c);
 	}
 
 	/*
@@ -2564,6 +2460,7 @@ server_client_check_redraw(struct client *c)
 		}
 		server_client_set_progress_bar(c);
 		redraw_screen(c);
+		redraw_client_damage(c);
 	}
 
 	/* Put the tty back how it was. */
@@ -2694,10 +2591,6 @@ server_client_dispatch(struct imsg *imsg, void *arg)
 		tty_resize(&c->tty);
 		tty_repeat_requests(&c->tty, 0);
 		recalculate_sizes();
-		if (c->overlay_resize == NULL)
-			server_client_clear_overlay(c);
-		else
-			c->overlay_resize(c, c->overlay_data);
 		server_redraw_client(c);
 		if (c->session != NULL)
 			server_client_fire_resized(c, old_sx, old_sy);

server-fn.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: server-fn.c,v 1.152 2026/09/03 19:12:36 nicm Exp $ */
+/* $OpenBSD: server-fn.c,v 1.154 2026/09/21 12:43:36 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -310,8 +310,8 @@ server_link_window(struct session *src, struct winlink *srcwl,
 		}
 		if (killflag) {
 			/*
-			 * Can't use session_detach as it will destroy session
-			 * if this makes it empty.
+			 * Can't use session_detach as it won't detach the only
+			 * window.
 			 */
 			events_fire_winlink("window-unlinked", dstwl);
 			dstwl->flags &= ~WINLINK_ALERTFLAGS;
@@ -386,6 +386,7 @@ server_destroy_pane(struct window_pane *wp, int notify)
 	case 0:
 		break;
 	case 2:
+	case 4:
 		if (WIFEXITED(wp->status) && WEXITSTATUS(wp->status) == 0)
 			break;
 		/* FALLTHROUGH */

session.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: session.c,v 1.107 2026/08/05 07:35:35 nicm Exp $ */
+/* $OpenBSD: session.c,v 1.108 2026/09/21 12:43:36 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -336,10 +336,17 @@ session_attach(struct session *s, struct window *w, int idx, char **cause)
 	return (wl);
 }
 
-/* Detach a window from a session. */
+/*
+ * Detach a window from a session. Returns 1 if the window has not been
+ * detached - the caller must destroy the session.
+ */
 int
 session_detach(struct session *s, struct winlink *wl)
 {
+	if (RB_MIN(winlinks, &s->windows) == wl &&
+	    RB_MAX(winlinks, &s->windows) == wl)
+		return (1);
+
 	if (s->curw == wl &&
 	    session_last(s) != 0 &&
 	    session_previous(s, 0) != 0)
@@ -352,8 +359,6 @@ session_detach(struct session *s, struct winlink *wl)
 
 	session_group_synchronize_from(s);
 
-	if (RB_EMPTY(&s->windows))
-		return (1);
 	return (0);
 }
 

spawn.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: spawn.c,v 1.52 2026/08/20 09:19:24 nicm Exp $ */
+/* $OpenBSD: spawn.c,v 1.53 2026/09/21 12:43:36 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -166,8 +166,8 @@ spawn_window(struct spawn_context *sc, char **cause)
 		}
 		if (wl != NULL) {
 			/*
-			 * Can't use session_detach as it will destroy session
-			 * if this makes it empty.
+			 * Can't use session_detach as it won't detach the only
+			 * window.
 			 */
 			wl->flags &= ~WINLINK_ALERTFLAGS;
 			events_fire_winlink("window-unlinked", wl);