Update CHANGES and tests.

whinging about not supporting it, GitHub issue 5626 from Pete Dietl.

.github/workflows/regress.yml

@@ -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

@@ -10,8 +10,8 @@ CHANGES FROM 3.7c TO 3.8
   - modal panes may be created with new-pane -O; a window can have one modal
     pane and it prevents interaction with the other panes while it is active.
     -C closes the pane when the mouse is clicked outside it and -K sends all
-    keys, including the prefix key, to the pane. A modal pane is now used for
+    keys, including the prefix key, to the pane. -D closes the modal pane with
-    the editor in buffer mode;
+    Escape or C-c. A modal pane is now used for the editor in buffer mode;
 
   - new-pane -A creates a floating pane which remains above a zoomed pane;
     modal panes do this by default;
@@ -33,14 +33,15 @@ 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;
+    default bindings under C-b g for common move and resize operations.
-
-  - floating panes are unzoomed before creation to avoid a crash.
 
 * Layout strings now use a JSON subset format which includes floating panes.
   The old format is still accepted; control mode clients receive old layouts
   unless they set the new-layouts flag.
 
+* Add remain-on-exit failed-key to keep a pane open after a failed command
+  until a key is pressed.
+
 * Add support for themes and improve default colours:
 
   - tmux now has builtin light and dark colour themes for terminals with 256 or
@@ -117,6 +118,12 @@ CHANGES FROM 3.7c TO 3.8
   in terminal-features, and add a utf8 feature for terminals which support
   UTF-8 output.
 
+* Add an appesc terminal feature for mintty's application escape key mode,
+  avoiding unsupported sequences on other terminals (Pete Dietl, issue 5626).
+
+* Preserve existing Ss and Se terminfo capabilities for cursor styles and
+  restoring the default cursor (issue 5476).
+
 * Add a #{A/count:frames} modifier to show a series of frames as an animation
   in the status line (issue 5412 from Fernando Daciuk).
 
@@ -132,6 +139,8 @@ 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.
@@ -189,10 +198,23 @@ CHANGES FROM 3.7c TO 3.8
   sent inside %begin/%end (issue 5458), do not let a stuck client prevent the
   server from exiting (issue 5444), and reset control mode offsets when a pane
   is respawned (issue 5498). Bound buffered command replies so a control mode
-  client that stops reading cannot consume unlimited memory (issue 5565).
+  client that stops reading cannot consume unlimited memory (issue 5565), and
+  fix a collision between the output discard and bracketed paste flags (issue
+  5622).
 
 * Fix grouped sessions sometimes being left as unusable command targets while
-  they are being killed (Bryce Miller, issue 5180).
+  they are being killed (Bryce Miller, issue 5180), and prevent reuse of a
+  session with no windows while detaching (Heon Jeong, issue 5620).
+
+* Free wait-for clients when they disconnect and do not run their remaining
+  queued commands (issue 5614).
+
+* Expand formats in run-shell -c like other start-directory flags (reported by
+  Saul Nogueras).
+
+* Fix session alert flag formats to check all windows (issue 5599).
+
+* Do not clear the marked pane when clicking on a pane border.
 
 * Fix choose mode filtering when more than one pane exists (issue 5326), and
   fix an infinite loop in customize mode when a filter does not match.
@@ -203,11 +225,18 @@ CHANGES FROM 3.7c TO 3.8
   status lines, menus, popups, wide characters and floating panes. This
   includes fixes for flicker with alternate screen applications and scrollbars
   (Michael Grant, issue 5351; Noam Stolero, issue 5350; Aung Myo Kyaw, issue
-  5098).
+  5098), and misplaced wrapped lines during partial redraws (Ben Maurer, issue
+  5625).
 
 * Do not crash looking for the next or previous session (issue 5344), or when
   no client is available.
 
+* Fix crashes when destroying a zoomed pane (Romain Francoise, issue 5591),
+  copying from a blank source pane (Kaixuan Li), or opening a mode prompt when
+  the client is offset into the window.
+
+* Avoid an infinite loop when assigning a width to WCHAR_MAX (issue 5602).
+
 CHANGES FROM 3.7b TO 3.7c
 
 * Build with jemalloc on macOS to avoid what appears to be a bug in calloc

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);
@@ -347,8 +355,10 @@ 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 +453,6 @@ 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')) {

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 },
+	.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] "
+	.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) {

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], 3.8-rc2)
 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);
 }

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
+ * Layouts can be represented as strings in a JSON format (v2). The version 1
- * format (v1) will be removed in the future and should no longer be used.
+ * 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;
+	struct layout_string	 layout_string = { 0 };
-	char			*out = NULL;
+	char			*out;
 
 	if (lcroot == NULL)
-		return NULL;
+		goto bad;
-
 	layout_string_init(&layout_string);
-
+	if (layout_append(lcroot, &layout_string, flags) != 0)
-	if (layout_append(lcroot, &layout_string, flags) == 0) {
+		goto bad;
-		if (flags & LAYOUT_CUSTOM_OLD_FORMAT)
+	if (~flags & LAYOUT_CUSTOM_OLD_FORMAT)
-			xasprintf(&out, "%04hx,%s",
+		xasprintf(&out, "{\"V\":2,\"L\":%s}", layout_string.dat);
-			    layout_checksum(layout_string.dat),
+	else {
-			    layout_string.dat);
+		xasprintf(&out, "%04hx,%s", layout_checksum(layout_string.dat),
-		else
+		    layout_string.dat);
-			xasprintf(&out, "{\"V\":2,\"L\":%s}",
-			    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) &&
+		if (lc->flags & LAYOUT_CELL_FLOATING) {
-		    window_pane_zindex(wp, &i) == 0)
+			z = layout_cell_zindex(lc);
-			layout_string_write(ls, ",\"z\":%u", i);
+			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>
@@ -768,6 +768,49 @@ 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 +831,11 @@ 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 +865,7 @@ 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 +1728,7 @@ 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 +1777,20 @@ 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 +1801,12 @@ 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;

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 1.245 2026/09/10 11:02:18 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -91,7 +91,7 @@ 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
@@ -1698,7 +1698,8 @@ const struct options_table_entry options_table[] = {
 	  .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."
 	},
 

regress/Makefile

@@ -1,33 +1,17 @@
 TESTS!= echo *.sh
 LOGDIR=logs
 
-.PHONY: all
+.PHONY: all prepare $(TESTS)
-.NOTPARALLEL: all
 
-all:
+all: prepare $(TESTS)
-	@mkdir -p "$(LOGDIR)"; \
+	@failed=0; failures=; \
-	rm -f "$(LOGDIR)"/*.log; \
-	failed=0; failures=; \
 	for test in $(TESTS); do \
 		base=$${test##*/}; \
 		log="$(LOGDIR)/$${base%.sh}.log"; \
-		rm -f "$$log"; \
+		if [ -f "$$log" ]; then \
-		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: $$log"; \
 			failed=1; \
 			failures="$$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
+# flags (window_activity_flag, window_bell_flag, window_silence_flag,
-# the #, !, ~ characters in window_flags). The sessions are detached so
+# 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/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-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
+# Use a control client to request legacy layouts, keeping only pane lines
-cat <<EOF|cmp -s $TMP - || exit 1
+# from the control protocol output.
+$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/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_option @after 'panes-mode'
-wait_format "$p0" '#{pane_mode}' 'panes-mode'
 wait_format "$p0" '#{pane_in_mode}' '0'
 
 # Existing zoom is restored on exit.

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-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'
+wait_for @log '|session-closed:doomed2|window-unlinked:doomed2:dwin2'
-assert_unchanged @log '|window-unlinked:doomed2:dwin2|session-closed:doomed2'
+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 \
+test_discard osc-discard '\e]2;'
-    "perl -e 'print qq{\e]2;}, q{x} x 1100000, qq{\e\\\\OK}'; sleep 2"
+test_discard apc-discard '\e_'
-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'
 
 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
+# Zoomed layouts are checked below with floating panes.
-# #{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.
 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 +356,50 @@ 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}')" ''
+
 # 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/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/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-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/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=$(mktemp)
+TMP=$(mktemp) || exit 1
-trap "rm -f $TMP" 0 1 15
+prompt_pid=
+
+cleanup () {
+	if [ -n "$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" > "$TMP" &
+	# Use a different prompt each time so a stale redraw cannot look ready.
-	sleep 0.05
+	assertion=$((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/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

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>
@@ -1673,7 +1673,7 @@ redraw_draw_pane_prompt(struct redraw_draw_ctx *dctx, struct window_pane *wp)
 	prompt_draw(wp->prompt, &pdd);
 	screen_write_stop(&ctx);
 
-	tty_draw_line(tty, &screen, 0, offset, width, px, cy, NULL);
+	tty_draw_line(tty, &screen, offset, 0, width, px, cy, NULL);
 	screen_free(&screen);
 }
 

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>
@@ -502,6 +502,9 @@ 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 +1394,19 @@ 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) ||
+	    KEYC_IS_PASTE(key))
-	    options_get_number(wp->options, "remain-on-exit") != 3)
+		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);
@@ -1756,9 +1763,10 @@ server_client_handle_key0(struct client *c, struct key_event *event,
 	}
 
 	/*
-	 * Key presses in overlay mode, for panes capturing all keys and in the
+	 * Key presses in overlay mode, dead panes waiting for a key, modal cancel
-	 * command prompt are a special case. The queue might be blocked so they
+	 * keys, panes capturing all keys and the command prompt are special cases.
-	 * need to be processed immediately rather than queued.
+	 * 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) {
@@ -1780,12 +1788,18 @@ server_client_handle_key0(struct client *c, struct key_event *event,
 		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);

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
+			 * Can't use session_detach as it won't detach the only
-			 * if this makes it empty.
+			 * 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
+			 * Can't use session_detach as it won't detach the only
-			 * if this makes it empty.
+			 * window.
 			 */
 			wl->flags &= ~WINLINK_ALERTFLAGS;
 			events_fire_winlink("window-unlinked", wl);

tmux.1

@@ -1,4 +1,4 @@
-.\" $OpenBSD: tmux.1,v 1.1168 2026/09/09 07:03:39 nicm Exp $
+.\" $OpenBSD: tmux.1,v 1.1172 2026/09/22 06:58:05 nicm Exp $
 .\"
 .\" Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
 .\"
@@ -14,7 +14,7 @@
 .\" IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 .\" OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: September 9 2026 $
+.Dd $Mdocdate: September 22 2026 $
 .Dt TMUX 1
 .Os
 .Sh NAME
@@ -3655,7 +3655,7 @@ but a different format may be specified with
 .Fl F .
 .Tg newp
 .It Xo Ic new\-pane
-.Op Fl AbCdefhIkKLMOPvWZ
+.Op Fl AbCDefhIkKLMOPvWZ
 .Op Fl B Ar border\-lines
 .Op Fl c Ar start\-directory
 .Op Fl e Ar environment
@@ -3717,6 +3717,13 @@ all keys, including the prefix key, are passed directly to the modal pane.
 With
 .Fl C ,
 the modal pane is closed when the mouse is clicked outside it.
+With
+.Fl D ,
+the modal pane is closed when
+.Ql Escape
+or
+.Ql C-c
+is pressed.
 .Pp
 The
 .Fl L
@@ -5078,6 +5085,9 @@ The available features are:
 .Bl -tag -width Ds
 .It 256
 Supports 256 colours with the SGR escape sequences.
+.It appesc
+Supports application escape key mode, where the Escape key sends a sequence
+that cannot be mistaken for the start of another key.
 .It clipboard
 Allows setting the system clipboard.
 .It ccolour
@@ -6328,7 +6338,7 @@ uses when the colour with that index is requested.
 The index may be from zero to 255.
 .Pp
 .It Xo Ic remain\-on\-exit
-.Op Ic on | off | failed | key
+.Op Ic on | off | failed | key | failed\-key
 .Xc
 A pane with this flag set is not destroyed when the program running in it
 exits.
@@ -6338,6 +6348,10 @@ then only when the program exit status is not zero.
 If set to
 .Ic key ,
 the pane stays open and closes when a key is pressed.
+If set to
+.Ic failed\-key ,
+the pane stays open and closes when a key is pressed only if the program exit
+status is not zero.
 The pane may be reactivated with the
 .Ic respawn\-pane
 command.
@@ -8957,6 +8971,8 @@ These are set automatically if the
 capability is present.
 .It Em \&Dseks , \&Eneks
 Disable and enable extended keys.
+.It Em \&Dsesc , \&Enesc
+Disable and enable application escape key mode.
 .It Em \&Dsfcs , \&Enfcs
 Disable and enable focus reporting.
 These are set automatically if the

tmux.h

@@ -1,4 +1,4 @@
-/* $OpenBSD: tmux.h,v 1.1438 2026/09/09 08:30:05 nicm Exp $ */
+/* $OpenBSD: tmux.h,v 1.1447 2026/09/22 14:10:26 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -464,6 +464,7 @@ enum tty_code_code {
 	TTYC_DL1,
 	TTYC_DSBP,
 	TTYC_DSEKS,
+	TTYC_DSESC,
 	TTYC_DSFCS,
 	TTYC_DSMG,
 	TTYC_E3,
@@ -474,6 +475,7 @@ enum tty_code_code {
 	TTYC_ENACS,
 	TTYC_ENBP,
 	TTYC_ENEKS,
+	TTYC_ENESC,
 	TTYC_ENFCS,
 	TTYC_ENMG,
 	TTYC_FSL,
@@ -1339,6 +1341,7 @@ struct window_pane {
 #define PANE_CLOSEONCLICK 0x80000
 #define PANE_CAPTUREALLKEYS 0x100000
 #define PANE_FLOATOVERZOOM 0x200000
+#define PANE_CLOSEONCANCEL 0x400000
 
 	bitstr_t	*sync_dirty;
 	u_int		 sync_dirty_size;
@@ -1737,6 +1740,7 @@ struct tty_term {
 #define TERM_VT100LIKE 0x20
 #define TERM_SIXEL 0x40
 #define TERM_INVALIDMS 0x80
+#define TERM_NOREPLACE 0x100
 	int		 flags;
 
 	LIST_ENTRY(tty_term) entry;
@@ -2302,7 +2306,7 @@ struct client {
 #define CLIENT_ASSUMEPASTING 0x2000000000ULL
 #define CLIENT_WRITE_ACK 0x4000000000ULL
 #define CLIENT_NO_DETACH_ON_DESTROY 0x8000000000ULL
-#define CLIENT_CONTROL_DISCARD 0x1000000000ULL
+#define CLIENT_CONTROL_DISCARD 0x10000000000ULL
 #define CLIENT_ALLREDRAWFLAGS		\
 	(CLIENT_REDRAWWINDOW|		\
 	 CLIENT_REDRAWSTATUS|		\
@@ -3006,7 +3010,7 @@ void	tty_default_colours(struct grid_cell *, struct window_pane *, u_int *);
 /* tty-term.c */
 extern struct tty_terms tty_terms;
 u_int		 tty_term_ncodes(void);
-void		 tty_term_apply(struct tty_term *, const char *, int);
+void		 tty_term_apply(struct tty_term *, const char *, int, int);
 void		 tty_term_apply_overrides(struct tty_term *);
 struct tty_term *tty_term_create(struct tty *, char *, char **, u_int, char **);
 void		 tty_term_free(struct tty_term *);
@@ -3226,6 +3230,7 @@ void 		 cmdq_print_data(struct cmdq_item *, struct evbuffer *);
 void printflike(2, 3) cmdq_error(struct cmdq_item *, const char *, ...);
 
 /* cmd-wait-for.c */
+void	cmd_wait_for_client_lost(struct client *);
 void	cmd_wait_for_flush(void);
 
 /* client.c */
@@ -3832,6 +3837,7 @@ int		 window_pane_get_pane_status(struct window_pane *);
 struct style_range *window_pane_status_get_range(struct window_pane *, u_int,
 		     u_int);
 int		 window_pane_is_floating(struct window_pane *);
+int		 window_pane_is_floating_with_hidden(struct window_pane *);
 
 /* window-border.c */
 void		 window_set_fill_cells(struct window *);

tty-draw.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: tty-draw.c,v 1.15 2026/07/26 09:02:08 nicm Exp $ */
+/* $OpenBSD: tty-draw.c,v 1.17 2026/09/22 06:49:47 nicm Exp $ */
 
 /*
  * Copyright (c) 2026 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -219,7 +219,12 @@ tty_draw_line(struct tty *tty, struct screen *s, u_int px, u_int py, u_int nx,
 	}
 
 	/* Did the previous line wrap on to this one? */
-	if (py != 0 && atx == 0 && tty->cx >= tty->sx && nx == tty->sx) {
+	if (py != 0 &&
+	    atx == 0 &&
+	    tty->cx >= tty->sx &&
+	    tty->cy != UINT_MAX &&
+	    tty->cy + 1 == aty &&
+	    nx == tty->sx) {
 		gl = grid_get_line(gd, gd->hsize + py - 1);
 		if (gl->flags & GRID_LINE_WRAPPED)
 			wrapped = 1;

tty-features.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: tty-features.c,v 1.43 2026/08/31 12:41:03 kirill Exp $ */
+/* $OpenBSD: tty-features.c,v 1.45 2026/09/22 14:10:26 nicm Exp $ */
 
 /*
  * Copyright (c) 2020 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -189,6 +189,18 @@ static const struct tty_feature tty_feature_focus = {
 	0
 };
 
+/* Terminal supports application escape key mode. */
+static const char *const tty_feature_appesc_capabilities[] = {
+	"Enesc=\\E[?7727h",
+	"Dsesc=\\E[?7727l",
+	NULL
+};
+static const struct tty_feature tty_feature_appesc = {
+	"appesc",
+	tty_feature_appesc_capabilities,
+	0
+};
+
 /* Terminal supports cursor styles. */
 static const char *const tty_feature_cstyle_capabilities[] = {
 	"Ss=\\E[%p1%d q",
@@ -198,7 +210,7 @@ static const char *const tty_feature_cstyle_capabilities[] = {
 static const struct tty_feature tty_feature_cstyle = {
 	"cstyle",
 	tty_feature_cstyle_capabilities,
-	0
+	TERM_NOREPLACE
 };
 
 /* Terminal supports cursor colours. */
@@ -378,6 +390,7 @@ static const struct tty_feature tty_feature_utf8 = {
 /* Available terminal features. */
 static const struct tty_feature *const tty_features[] = {
 	&tty_feature_256,
+	&tty_feature_appesc,
 	&tty_feature_bpaste,
 	&tty_feature_ccolour,
 	&tty_feature_clipboard,
@@ -541,11 +554,11 @@ tty_apply_features(struct tty_term *term)
 			capability = tf->capabilities;
 			while (*capability != NULL) {
 				log_debug("adding capability: %s", *capability);
-				tty_term_apply(term, *capability, 1);
+				tty_term_apply(term, *capability, 1, tf->flags);
 				capability++;
 			}
 		}
-		term->flags |= tf->flags;
+		term->flags |= (tf->flags & ~TERM_NOREPLACE);
 		if (tf == &tty_feature_utf8)
 			c->flags |= CLIENT_UTF8;
 	}
@@ -568,6 +581,7 @@ tty_default_features(struct client *c, const char *name, u_int version)
 	"256,RGB,bpaste,clipboard,mouse,strikethrough,title"
 		{ .name = "mintty",
 		  .features = TTY_FEATURES_BASE_MODERN_XTERM ","
+			      "appesc,"
 			      "ccolour,"
 			      "cstyle,"
 			      "extkeys,"

tty-term.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: tty-term.c,v 1.109 2026/08/25 08:37:08 nicm Exp $ */
+/* $OpenBSD: tty-term.c,v 1.111 2026/09/22 14:10:26 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -90,6 +90,7 @@ static const struct tty_term_code_entry tty_term_codes[] = {
 	[TTYC_DL1] = { TTYCODE_STRING, "dl1" },
 	[TTYC_DL] = { TTYCODE_STRING, "dl" },
 	[TTYC_DSEKS] = { TTYCODE_STRING, "Dseks" },
+	[TTYC_DSESC] = { TTYCODE_STRING, "Dsesc" },
 	[TTYC_DSFCS] = { TTYCODE_STRING, "Dsfcs" },
 	[TTYC_DSBP] = { TTYCODE_STRING, "Dsbp" },
 	[TTYC_DSMG] = { TTYCODE_STRING, "Dsmg" },
@@ -101,6 +102,7 @@ static const struct tty_term_code_entry tty_term_codes[] = {
 	[TTYC_ENACS] = { TTYCODE_STRING, "enacs" },
 	[TTYC_ENBP] = { TTYCODE_STRING, "Enbp" },
 	[TTYC_ENEKS] = { TTYCODE_STRING, "Eneks" },
+	[TTYC_ENESC] = { TTYCODE_STRING, "Enesc" },
 	[TTYC_ENFCS] = { TTYCODE_STRING, "Enfcs" },
 	[TTYC_ENMG] = { TTYCODE_STRING, "Enmg" },
 	[TTYC_FSL] = { TTYCODE_STRING, "fsl" },
@@ -362,7 +364,8 @@ tty_term_override_next(const char *s, size_t *offset)
 }
 
 void
-tty_term_apply(struct tty_term *term, const char *capabilities, int quiet)
+tty_term_apply(struct tty_term *term, const char *capabilities, int quiet,
+    int flags)
 {
 	const struct tty_term_code_entry	*ent;
 	struct tty_code				*code;
@@ -405,6 +408,9 @@ tty_term_apply(struct tty_term *term, const char *capabilities, int quiet)
 			if (strcmp(s, ent->name) != 0)
 				continue;
 			code = &term->codes[i];
+			if ((flags & TERM_NOREPLACE) &&
+			    code->type != TTYCODE_NONE)
+				continue;
 
 			if (remove) {
 				code->type = TTYCODE_NONE;
@@ -457,7 +463,7 @@ tty_term_apply_overrides(struct tty_term *term)
 		offset = 0;
 		first = tty_term_override_next(s, &offset);
 		if (first != NULL && fnmatch(first, term->name, 0) == 0)
-			tty_term_apply(term, s + offset, 0);
+			tty_term_apply(term, s + offset, 0, 0);
 		a = options_array_next(a);
 	}
 

tty.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: tty.c,v 1.480 2026/08/25 08:37:08 nicm Exp $ */
+/* $OpenBSD: tty.c,v 1.482 2026/09/22 06:58:06 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -503,8 +503,7 @@ tty_stop_tty(struct tty *tty)
 	if (tty_term_has(tty->term, TTYC_DSBP))
 		tty_raw(tty, tty_term_string(tty->term, TTYC_DSBP));
 
-	if (tty->term->flags & TERM_VT100LIKE)
+	tty_raw(tty, tty_term_string(tty->term, TTYC_DSESC));
-		tty_raw(tty, "\033[?7727l");
 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSFCS));
 	tty_raw(tty, tty_term_string(tty->term, TTYC_DSEKS));
 
@@ -563,8 +562,7 @@ tty_update_features(struct tty *tty)
 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENEKS));
 	if (options_get_number(global_options, "focus-events"))
 		tty_puts(tty, tty_term_string(tty->term, TTYC_ENFCS));
-	if (tty->term->flags & TERM_VT100LIKE)
+	tty_puts(tty, tty_term_string(tty->term, TTYC_ENESC));
-		tty_puts(tty, "\033[?7727h");
 
 	/*
 	 * Features might have changed since the first draw during attach. For

utf8.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: utf8.c,v 1.72 2026/09/01 12:49:49 nicm Exp $ */
+/* $OpenBSD: utf8.c,v 1.73 2026/09/20 08:11:00 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -374,8 +374,13 @@ utf8_add_to_width_cache(const char *s)
 			wc_end = wc_start;
 		}
 
-		for (wc = wc_start; wc <= wc_end; wc++)
+		wc = wc_start;
+		for (;;) {
 			utf8_insert_width_cache(wc, width);
+			if (wc == wc_end)
+				break;
+			wc++;
+		}
 	} else {
 		utf8_no_width = 1;
 		ud = utf8_fromcstr(copy);

window-copy.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: window-copy.c,v 1.429 2026/09/01 13:04:29 nicm Exp $ */
+/* $OpenBSD: window-copy.c,v 1.431 2026/09/21 10:43:37 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -401,7 +401,7 @@ window_copy_clone_screen(struct screen *src, struct screen *hint, u_int *cx,
 
 	sy = screen_hsize(src) + screen_size_y(src);
 	if (trim) {
-		while (sy > screen_hsize(src)) {
+		while (sy > screen_hsize(src) + 1) {
 			gl = grid_peek_line(src->grid, sy - 1);
 			if (gl == NULL || gl->cellused != 0)
 				break;

window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: window.c,v 1.374 2026/09/08 08:37:56 nicm Exp $ */
+/* $OpenBSD: window.c,v 1.377 2026/09/21 10:33:16 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -449,9 +449,17 @@ window_create(u_int sx, u_int sy, u_int xpixel, u_int ypixel)
 static void
 window_destroy(struct window *w)
 {
+	struct window_pane	*wp;
+
 	log_debug("window @%u destroyed (%d references)", w->id, w->references);
 
-	window_unzoom(w, 0);
+	if (w->flags & WINDOW_ZOOMED) {
+		w->flags &= ~WINDOW_ZOOMED;
+		TAILQ_FOREACH(wp, &w->panes, entry) {
+			wp->flags &= ~PANE_ZOOMED;
+			wp->saved_layout_cell = NULL;
+		}
+	}
 	RB_REMOVE(windows, &windows, w);
 
 	layout_free_cell(w->layout_root, 0);
@@ -2906,3 +2914,15 @@ window_pane_is_floating(struct window_pane *wp)
 		return (0);
 	return (1);
 }
+
+int
+window_pane_is_floating_with_hidden(struct window_pane *wp)
+{
+	struct layout_cell	*lc = wp->layout_cell;
+
+	if (lc == NULL)
+		lc = wp->saved_layout_cell;
+	if (lc == NULL || (lc->flags & LAYOUT_CELL_FLOATING) == 0)
+		return (0);
+	return (1);
+}