From b7c5030004c03095d2785c7d4ec50b1858764ee4 Mon Sep 17 00:00:00 2001
From: nicm <nicm@openbsd.org>
Date: Wed, 9 Sep 2026 09:01:19 +0000
Subject: [PATCH 1/5] =?UTF-8?q?Add=20a=20nesting=20limit=20for=20v1=20layo?=
 =?UTF-8?q?uts,=20reported=20by=20M=20Khalilov,=20fix=20based=20on=20issue?=
 =?UTF-8?q?=205572=20from=20Afonso=20Janu=C3=A1rio.=20Also=20tweak=20some?=
 =?UTF-8?q?=20language=20while=20here.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 layout-custom.c | 25 ++++++++++++++++---------
 1 file changed, 16 insertions(+), 9 deletions(-)

diff --git a/layout-custom.c b/layout-custom.c
index 7f6da285c..48b12a967 100644
--- a/layout-custom.c
+++ b/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 1.41 2026/09/09 09:01:19 nicm Exp $ */
 
 /*
  * Copyright (c) 2010 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -28,8 +28,8 @@
 #include "tmux.h"
 
 /*
- * Layouts can be represented as strings in a JSON format (v2). The legacy
- * format (v1) will be removed in the future and should no longer be used.
+ * Layouts can be represented as strings in a JSON format (v2). The version 1
+ * format will be removed in the future and should no longer be used.
  *
  * The current (v2) format is JSON. The top level has two keys:
  *    "V": version number, currently 2
@@ -57,6 +57,9 @@
  *    "z": z-index, if a floating pane
  */
 
+/* Maximum nesting depth for version 1 layouts. */
+#define LAYOUT_V1_MAX_DEPTH 1000
+
 /* Layout string. */
 struct layout_string {
 	char	*dat;
@@ -362,7 +365,7 @@ 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 +781,7 @@ 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 +830,15 @@ 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 +861,7 @@ 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 +1074,8 @@ 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);
 		}

From d9a5e8267879179a8edbb8d8721afd9db0bea195 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Thu, 10 Sep 2026 12:00:01 +0100
Subject: [PATCH 2/5] Fix tests.

---
 regress/control-client-sanity.sh |  7 +++++--
 regress/pane-ops.sh              | 29 ++++++++++++++++++++++++-----
 2 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/regress/control-client-sanity.sh b/regress/control-client-sanity.sh
index 32695e7c0..b85589de6 100644
--- a/regress/control-client-sanity.sh
+++ b/regress/control-client-sanity.sh
@@ -30,8 +30,11 @@ killw
 EOF
 sleep 1
 $TMUX has || exit 1
-$TMUX lsp -aF '#{pane_id} #{window_layout}' >$TMP || exit 1
-cat <<EOF|cmp -s $TMP - || exit 1
+# Use a control client to request legacy layouts, keeping only pane lines
+# from the control protocol output.
+$TMUX -C lsp -aF '#{pane_id} #{window_layout}' |
+	grep '^%[0-9]' >$TMP || exit 1
+cat <<EOF|cmp $TMP - || exit 1
 %0 f5ab,200x200,0,0[200x50,0,0,0,200x149,0,51,3]
 %3 f5ab,200x200,0,0[200x50,0,0,0,200x149,0,51,3]
 %2 dcbd,200x200,0,0[200x100,0,0,2,200x99,0,101,4]
diff --git a/regress/pane-ops.sh b/regress/pane-ops.sh
index c69362cee..25795c026 100644
--- a/regress/pane-ops.sh
+++ b/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'

From d202aa7ac13f9d3e5c6153d5a07604a7f5ffd0d0 Mon Sep 17 00:00:00 2001
From: nicm <nicm@openbsd.org>
Date: Thu, 10 Sep 2026 11:02:18 +0000
Subject: [PATCH 3/5] Add remain-on-exit failed-key and a -D flag to new-pane
 to have a modal pane wait for Escape/C-c. Both to allow better compatibility
 with popups.

---
 cmd-split-window.c |  8 +++++---
 options-table.c    |  7 ++++---
 server-client.c    | 29 ++++++++++++++++++++---------
 server-fn.c        |  3 ++-
 tmux.1             | 19 +++++++++++++++----
 tmux.h             |  3 ++-
 6 files changed, 48 insertions(+), 21 deletions(-)

diff --git a/cmd-split-window.c b/cmd-split-window.c
index b41f8e6aa..89e74d400 100644
--- a/cmd-split-window.c
+++ b/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>
@@ -41,8 +41,8 @@ const struct cmd_entry cmd_new_pane_entry = {
 	.name = "new-pane",
 	.alias = "newp",
 
-	.args = { "AbB:Cc:de:EfF:hIkl:KLMm:Op:PR:s:S:t:T:vWx:X:y:Y:Z", 0, -1, NULL },
-	.usage = "[-AbCdefhIkKLMOPvWZ] [-B border-lines] "
+	.args = { "AbB:Cc:Dde:EfF:hIkl:KLMm:Op:PR:s:S:t:T:vWx:X:y:Y:Z", 0, -1, NULL },
+	.usage = "[-AbCDefhIkKLMOPvWZ] [-B border-lines] "
 		 "[-c start-directory] [-e environment] "
 		 "[-F format] [-l size] [-m message] [-p percentage] "
 		 "[-s style] [-S active-border-style] "
@@ -220,6 +220,8 @@ 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) {
diff --git a/options-table.c b/options-table.c
index 81f043864..13a132fd0 100644
--- a/options-table.c
+++ b/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>
@@ -92,7 +92,7 @@ static const char *options_table_window_size_list[] = {
 	"largest", "smallest", "manual", "latest", NULL
 };
 static const char *options_table_remain_on_exit_list[] = {
-	"off", "on", "failed", "key", NULL
+	"off", "on", "failed", "key", "failed-key", NULL
 };
 static const char *options_table_destroy_unattached_list[] = {
 	"off", "on", "keep-last", "keep-group", NULL
@@ -1699,7 +1699,8 @@ 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."
 	},
 
diff --git a/server-client.c b/server-client.c
index cd94444fa..99eead885 100644
--- a/server-client.c
+++ b/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 1.512 2026/09/10 11:02:18 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1396,15 +1396,19 @@ server_client_repeat_time(struct client *c, struct key_binding *bd)
 	return (repeat);
 }
 
-/* Handle a key press on a dead pane waiting for a key. */
+/* Handle a key press which closes a dead pane. */
 static int
 server_client_handle_dead_key(struct window_pane *wp, key_code key)
 {
+	int	remain_on_exit;
+
 	if (wp == NULL ||
 	    (~wp->flags & PANE_EXITED) ||
 	    KEYC_IS_MOUSE(key) ||
-	    KEYC_IS_PASTE(key) ||
-	    options_get_number(wp->options, "remain-on-exit") != 3)
+	    KEYC_IS_PASTE(key))
+		return (0);
+	remain_on_exit = options_get_number(wp->options, "remain-on-exit");
+	if (remain_on_exit != 3 && remain_on_exit != 4)
 		return (0);
 	options_set_number(wp->options, "remain-on-exit", 0);
 	server_destroy_pane(wp, 0);
@@ -1761,9 +1765,10 @@ server_client_handle_key0(struct client *c, struct key_event *event,
 	}
 
 	/*
-	 * Key presses in overlay mode, for panes capturing all keys and in the
-	 * command prompt are a special case. The queue might be blocked so they
-	 * need to be processed immediately rather than queued.
+	 * Key presses in overlay mode, dead panes waiting for a key, modal cancel
+	 * keys, panes capturing all keys and the command prompt are special cases.
+	 * The queue might be blocked so they need to be processed immediately
+	 * rather than queued.
 	 */
 	if (~c->flags & CLIENT_READONLY) {
 		if (c->message_string != NULL) {
@@ -1785,12 +1790,18 @@ 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);
diff --git a/server-fn.c b/server-fn.c
index 5c4ae3d2a..754e0a514 100644
--- a/server-fn.c
+++ b/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 1.153 2026/09/10 11:02:18 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -383,6 +383,7 @@ 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 */
diff --git a/tmux.1 b/tmux.1
index 22780e2ce..41f0c234e 100644
--- a/tmux.1
+++ b/tmux.1
@@ -1,4 +1,4 @@
-.\" $OpenBSD: tmux.1,v 1.1168 2026/09/09 07:03:39 nicm Exp $
+.\" $OpenBSD: tmux.1,v 1.1169 2026/09/10 11:02:18 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 10 2026 $
 .Dt TMUX 1
 .Os
 .Sh NAME
@@ -3653,7 +3653,7 @@ 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
@@ -3715,6 +3715,13 @@ 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
@@ -6326,7 +6333,7 @@ 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.
@@ -6336,6 +6343,10 @@ 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.
diff --git a/tmux.h b/tmux.h
index 57b8b3939..83c29bdb0 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: tmux.h,v 1.1438 2026/09/09 08:30:05 nicm Exp $ */
+/* $OpenBSD: tmux.h,v 1.1439 2026/09/10 11:02:18 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1305,6 +1305,7 @@ 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;

From 14a01dd3377793138a4856720046074121638bab Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Fri, 11 Sep 2026 09:05:06 +0100
Subject: [PATCH 4/5] Note changes from Heon Jeong.

---
 CHANGES | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/CHANGES b/CHANGES
index 88baf7f42..62a7f8fc5 100644
--- a/CHANGES
+++ b/CHANGES
@@ -130,6 +130,8 @@ CHANGES FROM 3.7c TO 3.8
 
 * Add capture-pane -I to include the time each line entered history.
 
+* Various memory leak fixes from Heon Jeong.
+
 * Add a default C-b T binding to change the current pane title.
 
 * Menus now belong to the window, so appear on all clients.

From 10d00cc7cb941214a374aee587fc1db26a93a6c7 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Fri, 11 Sep 2026 09:10:14 +0100
Subject: [PATCH 5/5] Modal pane test changes.

---
 regress/modal-pane.sh | 45 +++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 43 insertions(+), 2 deletions(-)

diff --git a/regress/modal-pane.sh b/regress/modal-pane.sh
index b4217aa0a..0ae913b0b 100644
--- a/regress/modal-pane.sh
+++ b/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'