From ab1f2ef71c48bc9617db0874ca21681679f4d678 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 20 Jan 2026 16:32:05 +0000
Subject: [PATCH 1/7] Add a function to convert a screen to a string, from
 Michael Grant.

---
 screen.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 tmux.h   |  1 +
 2 files changed, 72 insertions(+)

diff --git a/screen.c b/screen.c
index 12a55097..b65a9106 100644
--- a/screen.c
+++ b/screen.c
@@ -744,3 +744,74 @@ screen_mode_to_string(int mode)
 	tmp[strlen(tmp) - 1] = '\0';
 	return (tmp);
 }
+
+const char *
+screen_print(struct screen *s)
+{
+	static char		*buf;
+	static size_t		 len = 16384;
+	const char		*acs;
+	u_int			 x, y;
+	int			 n;
+	size_t			 last = 0;
+	struct utf8_data	 ud;
+	struct grid_line	*gl;
+	struct grid_cell_entry	*gce;
+
+	if (buf == NULL)
+		buf = xmalloc(len);
+
+	for (y = 0; y < screen_hsize(s) + s->grid->sy; y++) {
+		n = snprintf(buf + last, len - last, "%.4d \"", y);
+		if (n <= 0 || (u_int)n >= len - last)
+			goto out;
+		last += n;
+
+		gl = &s->grid->linedata[y];
+		for (x = 0; x < gl->cellused; x++) {
+			gce = &gl->celldata[x];
+			if (gce->flags & GRID_FLAG_PADDING)
+				continue;
+
+			if (~gce->flags & GRID_FLAG_EXTENDED) {
+				if (last + 2 >= len)
+					goto out;
+				buf[last++] = gce->data.data;
+			} else if (gce->flags & GRID_FLAG_TAB) {
+				if (last + 2 >= len)
+					goto out;
+				buf[last++] = '\t';
+			} else if (gce->flags & GRID_ATTR_CHARSET) {
+				acs = tty_acs_get(NULL, gce->data.data);
+				if (acs != NULL)
+					n = strlen(acs);
+				else {
+					acs = &gce->data.data;
+					n = 1;
+				}
+				if (last + n + 1 >= len)
+					goto out;
+				memcpy(buf + last, acs, n);
+				last += n;
+			} else {
+				utf8_to_data(gl->extddata[gce->offset].data,
+				    &ud);
+				if (ud.size > 0) {
+					if (last + ud.size + 1 >= len)
+						goto out;
+					memcpy(buf + last, ud.data, ud.size);
+					last += ud.size;
+				}
+			}
+		}
+
+		if (last + 3 >= len)
+			goto out;
+		buf[last++] = '"';
+		buf[last++] = '\n';
+	}
+
+out:
+	buf[last] = '\0';
+	return (buf);
+}
diff --git a/tmux.h b/tmux.h
index e14113ff..e5145b10 100644
--- a/tmux.h
+++ b/tmux.h
@@ -3176,6 +3176,7 @@ void	 screen_select_cell(struct screen *, struct grid_cell *,
 void	 screen_alternate_on(struct screen *, struct grid_cell *, int);
 void	 screen_alternate_off(struct screen *, struct grid_cell *, int);
 const char *screen_mode_to_string(int);
+const char *screen_print(struct screen *);
 
 /* window.c */
 extern struct windows windows;

From 8e06739e266db5d076c2598778b665fdac10bf7c Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 20 Jan 2026 22:50:08 +0000
Subject: [PATCH 2/7] Fix window-size=latest not resizing on switch-client in
 session groups. From Ilya Grigoriev in GitHub issue 4818.

---
 server-client.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/server-client.c b/server-client.c
index c443d4c4..d60a53c2 100644
--- a/server-client.c
+++ b/server-client.c
@@ -407,13 +407,13 @@ server_client_set_session(struct client *c, struct session *s)
 	if (old != NULL && old->curw != NULL)
 		window_update_focus(old->curw->window);
 	if (s != NULL) {
+		s->curw->window->latest = c;
 		recalculate_sizes();
 		window_update_focus(s->curw->window);
 		session_update_activity(s, NULL);
 		session_theme_changed(s);
 		gettimeofday(&s->last_attached_time, NULL);
 		s->curw->flags &= ~WINLINK_ALERTFLAGS;
-		s->curw->window->latest = c;
 		alerts_check_session(s);
 		tty_update_client_offset(c);
 		status_timer_start(c);

From 26aacd0e3215b4cc63682180c714b775620735c1 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Thu, 22 Jan 2026 07:39:35 +0000
Subject: [PATCH 3/7] Handle theme keys earlier so they are processed even if a
 popup is open. From Josh Cooper in GitHub issue 4827.

---
 server-client.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/server-client.c b/server-client.c
index d60a53c2..9e82179b 100644
--- a/server-client.c
+++ b/server-client.c
@@ -2417,16 +2417,6 @@ server_client_key_callback(struct cmdq_item *item, void *data)
 		event->key = key;
 	}
 
-	/* Handle theme reporting keys. */
-	if (key == KEYC_REPORT_LIGHT_THEME) {
-		server_client_report_theme(c, THEME_LIGHT);
-		goto out;
-	}
-	if (key == KEYC_REPORT_DARK_THEME) {
-		server_client_report_theme(c, THEME_DARK);
-		goto out;
-	}
-
 	/* Find affected pane. */
 	if (!KEYC_IS_MOUSE(key) || cmd_find_from_mouse(&fs, m, 0) != 0)
 		cmd_find_from_client(&fs, c, 0);
@@ -2645,6 +2635,19 @@ server_client_handle_key(struct client *c, struct key_event *event)
 	if (s == NULL || (c->flags & CLIENT_UNATTACHEDFLAGS))
 		return (0);
 
+	/*
+	 * Handle theme reporting keys before overlays so they work even when a
+	 * popup is open.
+	 */
+	if (event->key == KEYC_REPORT_LIGHT_THEME) {
+		server_client_report_theme(c, THEME_LIGHT);
+		return (0);
+	}
+	if (event->key == KEYC_REPORT_DARK_THEME) {
+		server_client_report_theme(c, THEME_DARK);
+		return (0);
+	}
+
 	/*
 	 * Key presses in overlay mode and the command prompt are a special
 	 * case. The queue might be blocked so they need to be processed

From 818745a6056fdeb1e761e6c27fb91ea286b2ccbf Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Thu, 22 Jan 2026 07:42:30 +0000
Subject: [PATCH 4/7] Set PANE_STYLECHANGED when user options change, from Josh
 Cooper in GitHub issue 4825.

---
 options.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/options.c b/options.c
index bfbec5c7..37160b7a 100644
--- a/options.c
+++ b/options.c
@@ -1226,6 +1226,10 @@ options_push_changes(const char *name)
 		RB_FOREACH(wp, window_pane_tree, &all_window_panes)
 			wp->flags |= (PANE_STYLECHANGED|PANE_THEMECHANGED);
 	}
+	if (*name == '@') {
+		RB_FOREACH(wp, window_pane_tree, &all_window_panes)
+			wp->flags |= PANE_STYLECHANGED;
+	}
 	if (strcmp(name, "pane-colours") == 0) {
 		RB_FOREACH(wp, window_pane_tree, &all_window_panes)
 			colour_palette_from_option(&wp->palette, wp->options);

From ecbf8d76d0df0dcc3c05ea59e280de1b15b149c3 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Thu, 22 Jan 2026 07:52:24 +0000
Subject: [PATCH 5/7] Reevaluate menu and popup styles on each draw to allow
 them to change when options change, from Josh Cooper in GitHub issues 4828
 and 4829.

---
 menu.c  | 101 +++++++++++++++++++++++++++++++++++++++++---------------
 popup.c |  63 +++++++++++++++++++++++++++++++++--
 2 files changed, 135 insertions(+), 29 deletions(-)

diff --git a/menu.c b/menu.c
index 7449d88d..11e04279 100644
--- a/menu.c
+++ b/menu.c
@@ -27,9 +27,13 @@ struct menu_data {
 	struct cmdq_item	*item;
 	int			 flags;
 
-	struct grid_cell	 style;
-	struct grid_cell	 border_style;
-	struct grid_cell	 selected_style;
+	char			*style;
+	char			*border_style;
+	char			*selected_style;
+
+	struct grid_cell	 style_gc;
+	struct grid_cell	 border_style_gc;
+	struct grid_cell	 selected_style_gc;
 	enum box_lines		 border_lines;
 
 	struct cmd_find_state	 fs;
@@ -192,6 +196,60 @@ menu_check_cb(__unused struct client *c, void *data, u_int px, u_int py,
 	    menu->count + 2, px, py, nx, r);
 }
 
+static void
+menu_reapply_styles(struct menu_data *md, struct client *c)
+{
+	struct session		*s = c->session;
+	struct options		*o;
+	struct format_tree	*ft;
+	struct style		 sytmp;
+
+	if (s == NULL)
+		return;
+	o = s->curw->window->options;
+
+	ft = format_create_defaults(NULL, c, s, s->curw, NULL);
+
+	/* Reapply menu style from options. */
+	memcpy(&md->style_gc, &grid_default_cell, sizeof md->style_gc);
+	style_apply(&md->style_gc, o, "menu-style", ft);
+	if (md->style != NULL) {
+		style_set(&sytmp, &grid_default_cell);
+		if (style_parse(&sytmp, &md->style_gc, md->style) == 0) {
+			md->style_gc.fg = sytmp.gc.fg;
+			md->style_gc.bg = sytmp.gc.bg;
+		}
+	}
+
+	/* Reapply selected style from options. */
+	memcpy(&md->selected_style_gc, &grid_default_cell,
+	    sizeof md->selected_style_gc);
+	style_apply(&md->selected_style_gc, o, "menu-selected-style", ft);
+	if (md->selected_style != NULL) {
+		style_set(&sytmp, &grid_default_cell);
+		if (style_parse(&sytmp, &md->selected_style_gc,
+		    md->selected_style) == 0) {
+			md->selected_style_gc.fg = sytmp.gc.fg;
+			md->selected_style_gc.bg = sytmp.gc.bg;
+		}
+	}
+
+	/* Reapply border style from options. */
+	memcpy(&md->border_style_gc, &grid_default_cell,
+	    sizeof md->border_style_gc);
+	style_apply(&md->border_style_gc, o, "menu-border-style", ft);
+	if (md->border_style != NULL) {
+		style_set(&sytmp, &grid_default_cell);
+		if (style_parse(&sytmp, &md->border_style_gc,
+		    md->border_style) == 0) {
+			md->border_style_gc.fg = sytmp.gc.fg;
+			md->border_style_gc.bg = sytmp.gc.bg;
+		}
+	}
+
+	format_free(ft);
+}
+
 void
 menu_draw_cb(struct client *c, void *data,
     __unused struct screen_redraw_ctx *rctx)
@@ -203,16 +261,18 @@ menu_draw_cb(struct client *c, void *data,
 	struct screen_write_ctx	 ctx;
 	u_int			 i, px = md->px, py = md->py;
 
+	menu_reapply_styles(md, c);
+
 	screen_write_start(&ctx, s);
 	screen_write_clearscreen(&ctx, 8);
 
 	if (md->border_lines != BOX_LINES_NONE) {
 		screen_write_box(&ctx, menu->width + 4, menu->count + 2,
-		    md->border_lines, &md->border_style, menu->title);
+		    md->border_lines, &md->border_style_gc, menu->title);
 	}
 
 	screen_write_menu(&ctx, menu, md->choice, md->border_lines,
-	    &md->style, &md->border_style, &md->selected_style);
+	    &md->style_gc, &md->border_style_gc, &md->selected_style_gc);
 	screen_write_stop(&ctx);
 
 	for (i = 0; i < screen_size_y(&md->s); i++) {
@@ -234,6 +294,9 @@ menu_free_cb(__unused struct client *c, void *data)
 
 	screen_free(&md->s);
 	menu_free(md->menu);
+	free(md->style);
+	free(md->selected_style);
+	free(md->border_style);
 	free(md);
 }
 
@@ -470,24 +533,6 @@ menu_resize_cb(struct client *c, void *data)
 	md->py = ny;
 }
 
-static void
-menu_set_style(struct client *c, struct grid_cell *gc, const char *style,
-    const char *option)
-{
-	struct style	 sytmp;
-	struct options	*o = c->session->curw->window->options;
-
-	memcpy(gc, &grid_default_cell, sizeof *gc);
-	style_apply(gc, o, option, NULL);
-	if (style != NULL) {
-		style_set(&sytmp, &grid_default_cell);
-		if (style_parse(&sytmp, gc, style) == 0) {
-			gc->fg = sytmp.gc.fg;
-			gc->bg = sytmp.gc.bg;
-		}
-	}
-}
-
 struct menu_data *
 menu_prepare(struct menu *menu, int flags, int starting_choice,
     struct cmdq_item *item, u_int px, u_int py, struct client *c,
@@ -515,10 +560,12 @@ menu_prepare(struct menu *menu, int flags, int starting_choice,
 	md->flags = flags;
 	md->border_lines = lines;
 
-	menu_set_style(c, &md->style, style, "menu-style");
-	menu_set_style(c, &md->selected_style, selected_style,
-	    "menu-selected-style");
-	menu_set_style(c, &md->border_style, border_style, "menu-border-style");
+	if (style != NULL)
+		md->style = xstrdup(style);
+	if (selected_style != NULL)
+		md->selected_style = xstrdup(selected_style);
+	if (border_style != NULL)
+		md->border_style = xstrdup(border_style);
 
 	if (fs != NULL)
 		cmd_find_copy_state(&md->fs, fs);
diff --git a/popup.c b/popup.c
index 12cd7362..e8a3cbf4 100644
--- a/popup.c
+++ b/popup.c
@@ -33,6 +33,8 @@ struct popup_data {
 	int			  flags;
 	char			 *title;
 
+	char			 *style;
+	char			 *border_style;
 	struct grid_cell	  border_cell;
 	enum box_lines		  border_lines;
 
@@ -99,6 +101,49 @@ static const struct menu_item popup_internal_menu_items[] = {
 	{ NULL, KEYC_NONE, NULL }
 };
 
+static void
+popup_reapply_styles(struct popup_data *pd)
+{
+	struct client		*c = pd->c;
+	struct session		*s = c->session;
+	struct options		*o;
+	struct format_tree	*ft;
+	struct style		 sytmp;
+
+	if (s == NULL)
+		return;
+	o = s->curw->window->options;
+
+	ft = format_create_defaults(NULL, c, s, s->curw, NULL);
+
+	/* Reapply popup style from options. */
+	memcpy(&pd->defaults, &grid_default_cell, sizeof pd->defaults);
+	style_apply(&pd->defaults, o, "popup-style", ft);
+	if (pd->style != NULL) {
+		style_set(&sytmp, &grid_default_cell);
+		if (style_parse(&sytmp, &pd->defaults, pd->style) == 0) {
+			pd->defaults.fg = sytmp.gc.fg;
+			pd->defaults.bg = sytmp.gc.bg;
+		}
+	}
+	pd->defaults.attr = 0;
+
+	/* Reapply border style from options. */
+	memcpy(&pd->border_cell, &grid_default_cell, sizeof pd->border_cell);
+	style_apply(&pd->border_cell, o, "popup-border-style", ft);
+	if (pd->border_style != NULL) {
+		style_set(&sytmp, &grid_default_cell);
+		if (style_parse(&sytmp, &pd->border_cell,
+		    pd->border_style) == 0) {
+			pd->border_cell.fg = sytmp.gc.fg;
+			pd->border_cell.bg = sytmp.gc.bg;
+		}
+	}
+	pd->border_cell.attr = 0;
+
+	format_free(ft);
+}
+
 static void
 popup_redraw_cb(const struct tty_ctx *ttyctx)
 {
@@ -220,6 +265,8 @@ popup_draw_cb(struct client *c, void *data, struct screen_redraw_ctx *rctx)
 	struct colour_palette	*palette = &pd->palette;
 	struct grid_cell	 defaults;
 
+	popup_reapply_styles(pd);
+
 	screen_init(&s, pd->sx, pd->sy, 0);
 	screen_write_start(&ctx, &s);
 	screen_write_clearscreen(&ctx, 8);
@@ -291,6 +338,8 @@ popup_free_cb(struct client *c, void *data)
 	colour_palette_free(&pd->palette);
 
 	free(pd->title);
+	free(pd->style);
+	free(pd->border_style);
 	free(pd);
 }
 
@@ -550,7 +599,7 @@ popup_key_cb(struct client *c, void *data, struct key_event *event)
 	    (event->key == '\033' || event->key == ('c'|KEYC_CTRL)))
 		return (1);
 	if (pd->job == NULL && (pd->flags & POPUP_CLOSEANYKEY) &&
-            !KEYC_IS_MOUSE(event->key) && !KEYC_IS_PASTE(event->key))
+	    !KEYC_IS_MOUSE(event->key) && !KEYC_IS_PASTE(event->key))
 		return (1);
 	if (pd->job != NULL) {
 		if (KEYC_IS_MOUSE(event->key)) {
@@ -659,6 +708,8 @@ popup_modify(struct client *c, const char *title, const char *style,
 		pd->title = xstrdup(title);
 	}
 	if (border_style != NULL) {
+		free(pd->border_style);
+		pd->border_style = xstrdup(border_style);
 		style_set(&sytmp, &pd->border_cell);
 		if (style_parse(&sytmp, &pd->border_cell, border_style) == 0) {
 			pd->border_cell.fg = sytmp.gc.fg;
@@ -666,6 +717,8 @@ popup_modify(struct client *c, const char *title, const char *style,
 		}
 	}
 	if (style != NULL) {
+		free(pd->style);
+		pd->style = xstrdup(style);
 		style_set(&sytmp, &pd->defaults);
 		if (style_parse(&sytmp, &pd->defaults, style) == 0) {
 			pd->defaults.fg = sytmp.gc.fg;
@@ -676,7 +729,8 @@ popup_modify(struct client *c, const char *title, const char *style,
 		if (lines == BOX_LINES_NONE && pd->border_lines != lines) {
 			screen_resize(&pd->s, pd->sx, pd->sy, 1);
 			job_resize(pd->job, pd->sx, pd->sy);
-		} else if (pd->border_lines == BOX_LINES_NONE && pd->border_lines != lines) {
+		} else if (pd->border_lines == BOX_LINES_NONE &&
+		    pd->border_lines != lines) {
 			screen_resize(&pd->s, pd->sx - 2, pd->sy - 2, 1);
 			job_resize(pd->job, pd->sx - 2, pd->sy - 2);
 		}
@@ -726,8 +780,13 @@ popup_display(int flags, enum box_lines lines, struct cmdq_item *item, u_int px,
 	pd = xcalloc(1, sizeof *pd);
 	pd->item = item;
 	pd->flags = flags;
+
 	if (title != NULL)
 		pd->title = xstrdup(title);
+	if (style != NULL)
+		pd->style = xstrdup(style);
+	if (border_style != NULL)
+		pd->border_style = xstrdup(border_style);
 
 	pd->c = c;
 	pd->c->references++;

From 195a9cfd8885d631633b414495a1f2540faa2601 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Thu, 22 Jan 2026 08:55:01 +0000
Subject: [PATCH 6/7] When history-limit is changed, apply to existing panes,
 not just new ones. GitHub issue 4705.

---
 grid-view.c   |  4 ++--
 grid.c        |  7 +++++--
 options.c     |  4 ++++
 session.c     | 26 ++++++++++++++++++++++++++
 tmux.1        |  4 +---
 tmux.h        |  3 ++-
 window-copy.c |  5 +++++
 7 files changed, 45 insertions(+), 8 deletions(-)

diff --git a/grid-view.c b/grid-view.c
index 7590ea42..655ec9e4 100644
--- a/grid-view.c
+++ b/grid-view.c
@@ -82,7 +82,7 @@ grid_view_clear_history(struct grid *gd, u_int bg)
 
 	/* Scroll the lines into the history. */
 	for (yy = 0; yy < last; yy++) {
-		grid_collect_history(gd);
+		grid_collect_history(gd, 0);
 		grid_scroll_history(gd, bg);
 	}
 	if (last < gd->sy)
@@ -107,7 +107,7 @@ grid_view_scroll_region_up(struct grid *gd, u_int rupper, u_int rlower,
     u_int bg)
 {
 	if (gd->flags & GRID_HISTORY) {
-		grid_collect_history(gd);
+		grid_collect_history(gd, 0);
 		if (rupper == 0 && rlower == gd->sy - 1)
 			grid_scroll_history(gd, bg);
 		else {
diff --git a/grid.c b/grid.c
index 7ad6770b..92a9ce76 100644
--- a/grid.c
+++ b/grid.c
@@ -375,14 +375,17 @@ grid_trim_history(struct grid *gd, u_int ny)
  * and shift up.
  */
 void
-grid_collect_history(struct grid *gd)
+grid_collect_history(struct grid *gd, int all)
 {
 	u_int	ny;
 
 	if (gd->hsize == 0 || gd->hsize < gd->hlimit)
 		return;
 
-	ny = gd->hlimit / 10;
+	if (all)
+		ny = gd->hsize - gd->hlimit;
+	else
+		ny = gd->hlimit / 10;
 	if (ny < 1)
 		ny = 1;
 	if (ny > gd->hsize)
diff --git a/options.c b/options.c
index 37160b7a..a847ad9c 100644
--- a/options.c
+++ b/options.c
@@ -1252,6 +1252,10 @@ options_push_changes(const char *name)
 		utf8_update_width_cache();
 	if (strcmp(name, "input-buffer-size") == 0)
 		input_set_buffer_size(options_get_number(global_options, name));
+	if (strcmp(name, "history-limit") == 0) {
+		RB_FOREACH(s, sessions, &sessions)
+			session_update_history(s);
+	}
 	RB_FOREACH(s, sessions, &sessions)
 		status_update_cache(s);
 
diff --git a/session.c b/session.c
index 51430678..afa48637 100644
--- a/session.c
+++ b/session.c
@@ -768,3 +768,29 @@ session_theme_changed(struct session *s)
 		}
 	}
 }
+
+/* Update history for all panes. */
+void
+session_update_history(struct session *s)
+{
+	struct winlink		*wl;
+	struct window_pane	*wp;
+	struct grid		*gd;
+	u_int			 limit, osize;
+
+	limit = options_get_number(s->options, "history-limit");
+	RB_FOREACH(wl, winlinks, &s->windows) {
+		TAILQ_FOREACH(wp, &wl->window->panes, entry) {
+			gd = wp->base.grid;
+
+			osize = gd->hsize;
+			gd->hlimit = limit;
+			grid_collect_history(gd, 1);
+
+			if (gd->hsize != osize) {
+				log_debug("%s: %%%u %u -> %u", __func__, wp->id,
+				    osize, gd->hsize);
+			}
+		}
+	}
+}
diff --git a/tmux.1 b/tmux.1
index bf051794..f58511f2 100644
--- a/tmux.1
+++ b/tmux.1
@@ -4583,9 +4583,7 @@ If set to 0, messages and indicators are displayed until a key is pressed.
 .Ar time
 is in milliseconds.
 .It Ic history-limit Ar lines
-Set the maximum number of lines held in window history.
-This setting applies only to new windows - existing window histories are not
-resized and retain the limit at the point they were created.
+Set the maximum number of lines held in pane history.
 .It Ic initial-repeat-time Ar time
 Set the time in milliseconds for the initial repeat when a key is bound with the
 .Fl r
diff --git a/tmux.h b/tmux.h
index e5145b10..74447785 100644
--- a/tmux.h
+++ b/tmux.h
@@ -3002,7 +3002,7 @@ int	 grid_cells_look_equal(const struct grid_cell *,
 struct grid *grid_create(u_int, u_int, u_int);
 void	 grid_destroy(struct grid *);
 int	 grid_compare(struct grid *, struct grid *);
-void	 grid_collect_history(struct grid *);
+void	 grid_collect_history(struct grid *, int);
 void	 grid_remove_history(struct grid *, u_int );
 void	 grid_scroll_history(struct grid *, u_int);
 void	 grid_scroll_history_region(struct grid *, u_int, u_int, u_int);
@@ -3485,6 +3485,7 @@ u_int		 session_group_count(struct session_group *);
 u_int		 session_group_attached_count(struct session_group *);
 void		 session_renumber_windows(struct session *);
 void		 session_theme_changed(struct session *);
+void		 session_update_history(struct session *);
 
 /* utf8.c */
 enum utf8_state	 utf8_towc (const struct utf8_data *, wchar_t *);
diff --git a/window-copy.c b/window-copy.c
index 82c0f47f..04cfe85d 100644
--- a/window-copy.c
+++ b/window-copy.c
@@ -2708,6 +2708,11 @@ window_copy_cmd_refresh_from_pane(struct window_copy_cmd_state *cs)
 	data->backing = window_copy_clone_screen(&wp->base, &data->screen, NULL,
 	    NULL, wme->swp != wme->wp);
 
+	if (data->oy > screen_hsize(data->backing)) {
+		data->cy = 0;
+		data->oy = screen_hsize(data->backing);
+	}
+
 	window_copy_size_changed(wme);
 	return (WINDOW_COPY_CMD_REDRAW);
 }

From f70150a6637b55de522d99b623dce51428fec6c8 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Fri, 23 Jan 2026 10:45:53 +0000
Subject: [PATCH 7/7] Replace overlay_ranges with visible_ranges which can hold
 more than three ranges (will be needed for floating panes); move the visible
 ranges checks outside of tty_draw_line and rewrite it to fix issues with
 partially-obscured wide characters. With Michael Grant.

---
 Makefile        |   1 +
 grid.c          |   2 +-
 menu.c          |  10 +-
 popup.c         |  67 ++++++----
 screen-redraw.c |  23 +++-
 screen.c        |   5 +-
 server-client.c |  59 ++++++---
 tmux.h          |  51 +++++---
 tty-draw.c      | 319 ++++++++++++++++++++++++++++++++++++++++++++++++
 tty.c           | 281 ++++++------------------------------------
 10 files changed, 502 insertions(+), 316 deletions(-)
 create mode 100644 tty-draw.c

diff --git a/Makefile b/Makefile
index 6cd1b1b5..14cf2fd2 100644
--- a/Makefile
+++ b/Makefile
@@ -116,6 +116,7 @@ SRCS=	alerts.c \
 	style.c \
 	tmux.c \
 	tty-acs.c \
+	tty-draw.c \
 	tty-features.c \
 	tty-keys.c \
 	tty-term.c \
diff --git a/grid.c b/grid.c
index 92a9ce76..c783f7b7 100644
--- a/grid.c
+++ b/grid.c
@@ -235,7 +235,7 @@ grid_check_y(struct grid *gd, const char *from, u_int py)
 int
 grid_cells_look_equal(const struct grid_cell *gc1, const struct grid_cell *gc2)
 {
-	int flags1 = gc1->flags, flags2 = gc2->flags;;
+	int flags1 = gc1->flags, flags2 = gc2->flags;
 
 	if (gc1->fg != gc2->fg || gc1->bg != gc2->bg)
 		return (0);
diff --git a/menu.c b/menu.c
index 11e04279..c458e68b 100644
--- a/menu.c
+++ b/menu.c
@@ -38,6 +38,7 @@ struct menu_data {
 
 	struct cmd_find_state	 fs;
 	struct screen		 s;
+	struct visible_ranges	 r;
 
 	u_int			 px;
 	u_int			 py;
@@ -185,15 +186,16 @@ menu_mode_cb(__unused struct client *c, void *data, u_int *cx, u_int *cy)
 }
 
 /* Return parts of the input range which are not obstructed by the menu. */
-void
+struct visible_ranges *
 menu_check_cb(__unused struct client *c, void *data, u_int px, u_int py,
-    u_int nx, struct overlay_ranges *r)
+    u_int nx)
 {
 	struct menu_data	*md = data;
 	struct menu		*menu = md->menu;
 
 	server_client_overlay_range(md->px, md->py, menu->width + 4,
-	    menu->count + 2, px, py, nx, r);
+	    menu->count + 2, px, py, nx, &md->r);
+	return (&md->r);
 }
 
 static void
@@ -292,7 +294,9 @@ menu_free_cb(__unused struct client *c, void *data)
 	if (md->cb != NULL)
 		md->cb(md->menu, UINT_MAX, KEYC_NONE, md->data);
 
+	free(md->r.ranges);
 	screen_free(&md->s);
+
 	menu_free(md->menu);
 	free(md->style);
 	free(md->selected_style);
diff --git a/popup.c b/popup.c
index e8a3cbf4..70f4def4 100644
--- a/popup.c
+++ b/popup.c
@@ -42,6 +42,9 @@ struct popup_data {
 	struct grid_cell	  defaults;
 	struct colour_palette	  palette;
 
+	struct visible_ranges	  r;
+	struct visible_ranges	  or[2];
+
 	struct job		 *job;
 	struct input_ctx	 *ictx;
 	int			  status;
@@ -210,48 +213,57 @@ popup_mode_cb(__unused struct client *c, void *data, u_int *cx, u_int *cy)
 }
 
 /* Return parts of the input range which are not obstructed by the popup. */
-static void
-popup_check_cb(struct client* c, void *data, u_int px, u_int py, u_int nx,
-    struct overlay_ranges *r)
+static struct visible_ranges *
+popup_check_cb(struct client* c, void *data, u_int px, u_int py, u_int nx)
 {
 	struct popup_data	*pd = data;
-	struct overlay_ranges	 or[2];
+	struct visible_ranges	*r = &pd->r;
+	struct visible_ranges	*mr;
 	u_int			 i, j, k = 0;
 
 	if (pd->md != NULL) {
-		/* Check each returned range for the menu against the popup. */
-		menu_check_cb(c, pd->md, px, py, nx, r);
-		for (i = 0; i < 2; i++) {
+	       /*
+		* Work out the visible ranges for the menu (that is, the
+		* ranges not covered by the menu). A menu should have at most
+		* two ranges and we rely on this being the case.
+		*/
+		mr = menu_check_cb(c, pd->md, px, py, nx);
+		if (mr->used > 2)
+			fatalx("too many menu ranges");
+
+	       /*
+		* Walk the ranges still visible under the menu and check if
+		* each is visible under the popup as well. At most there can be
+		* three total ranges if popup and menu do not intersect.
+		*/
+		for (i = 0; i < mr->used; i++) {
 			server_client_overlay_range(pd->px, pd->py, pd->sx,
-			    pd->sy, r->px[i], py, r->nx[i], &or[i]);
+			    pd->sy, r->ranges[i].px, py, r->ranges[i].nx,
+			    &pd->or[i]);
 		}
 
 		/*
-		 * or has up to OVERLAY_MAX_RANGES non-overlapping ranges,
-		 * ordered from left to right. Collect them in the output.
+		 * We now have nonoverlapping ranges from left to right.
+		 * Combine them together into the output.
 		 */
-		for (i = 0; i < 2; i++) {
-			/* Each or[i] only has 2 ranges. */
-			for (j = 0; j < 2; j++) {
-				if (or[i].nx[j] > 0) {
-					r->px[k] = or[i].px[j];
-					r->nx[k] = or[i].nx[j];
-					k++;
-				}
+		server_client_ensure_ranges(r, 3);
+		for (i = 0; i < mr->used; i++) {
+			for (j = 0; j < pd->or[i].used; j++) {
+				if (pd->or[i].ranges[j].nx == 0)
+					continue;
+				if (k >= 3)
+					fatalx("too many popup & menu ranges");
+				r->ranges[k].px = pd->or[i].ranges[j].px;
+				r->ranges[k].nx = pd->or[i].ranges[j].nx;
+				k++;
 			}
 		}
-
-		/* Zero remaining ranges if any. */
-		for (i = k; i < OVERLAY_MAX_RANGES; i++) {
-			r->px[i] = 0;
-			r->nx[i] = 0;
-		}
-
-		return;
+		return (r);
 	}
 
 	server_client_overlay_range(pd->px, pd->py, pd->sx, pd->sy, px, py, nx,
 	    r);
+	return (r);
 }
 
 static void
@@ -334,6 +346,9 @@ popup_free_cb(struct client *c, void *data)
 		job_free(pd->job);
 	input_free(pd->ictx);
 
+	free(pd->or[0].ranges);
+	free(pd->or[1].ranges);
+	free(pd->r.ranges);
 	screen_free(&pd->s);
 	colour_palette_free(&pd->palette);
 
diff --git a/screen-redraw.c b/screen-redraw.c
index 57ad0107..138edd52 100644
--- a/screen-redraw.c
+++ b/screen-redraw.c
@@ -817,13 +817,14 @@ screen_redraw_draw_borders_cell(struct screen_redraw_ctx *ctx, u_int i, u_int j)
 	struct window_pane	*wp, *active = server_client_get_pane(c);
 	struct grid_cell	 gc;
 	const struct grid_cell	*tmp;
-	struct overlay_ranges	 r;
-	u_int			 cell_type, x = ctx->ox + i, y = ctx->oy + j;
+	u_int			 cell_type;
+	u_int			 x = ctx->ox + i, y = ctx->oy + j;
 	int			 isolates;
+	struct visible_ranges	*r;
 
 	if (c->overlay_check != NULL) {
-		c->overlay_check(c, c->overlay_data, x, y, 1, &r);
-		if (r.nx[0] + r.nx[1] == 0)
+		r = c->overlay_check(c, c->overlay_data, x, y, 1);
+		if (server_client_ranges_is_empty(r))
 			return;
 	}
 
@@ -943,7 +944,9 @@ screen_redraw_draw_pane(struct screen_redraw_ctx *ctx, struct window_pane *wp)
 	struct screen		*s = wp->screen;
 	struct colour_palette	*palette = &wp->palette;
 	struct grid_cell	 defaults;
-	u_int			 i, j, top, x, y, width;
+	struct visible_ranges	*r;
+	struct visible_range	*rr;
+	u_int			 i, j, k, top, x, y, width;
 
 	if (wp->base.mode & MODE_SYNC)
 		screen_write_stop_sync(wp);
@@ -988,7 +991,15 @@ screen_redraw_draw_pane(struct screen_redraw_ctx *ctx, struct window_pane *wp)
 		    __func__, c->name, wp->id, i, j, x, y, width);
 
 		tty_default_colours(&defaults, wp);
-		tty_draw_line(tty, s, i, j, width, x, y, &defaults, palette);
+
+		r = tty_check_overlay_range(tty, x, y, width);
+		for (k = 0; k < r->used; k++) {
+			rr = &r->ranges[k];
+			if (rr->nx != 0) {
+				tty_draw_line(tty, s, rr->px - wp->xoff, j,
+				    rr->nx, rr->px, y, &defaults, palette);
+			}
+		}
 	}
 }
 
diff --git a/screen.c b/screen.c
index b65a9106..4f382ded 100644
--- a/screen.c
+++ b/screen.c
@@ -564,12 +564,12 @@ screen_check_selection(struct screen *s, u_int px, u_int py)
 }
 
 /* Get selected grid cell. */
-void
+int
 screen_select_cell(struct screen *s, struct grid_cell *dst,
     const struct grid_cell *src)
 {
 	if (s->sel == NULL || s->sel->hidden)
-		return;
+		return (0);
 
 	memcpy(dst, &s->sel->cell, sizeof *dst);
 	if (COLOUR_DEFAULT(dst->fg))
@@ -583,6 +583,7 @@ screen_select_cell(struct screen *s, struct grid_cell *dst,
 		dst->attr |= (src->attr & GRID_ATTR_CHARSET);
 	else
 		dst->attr |= src->attr;
+	return (1);
 }
 
 /* Reflow wrapped lines. */
diff --git a/server-client.c b/server-client.c
index 9e82179b..050ca10a 100644
--- a/server-client.c
+++ b/server-client.c
@@ -165,38 +165,58 @@ server_client_clear_overlay(struct client *c)
 	server_redraw_client(c);
 }
 
+/* Are these ranges empty? That is, nothing is visible. */
+int
+server_client_ranges_is_empty(struct visible_ranges *r)
+{
+	u_int	i;
+
+	for (i = 0; i < r->used; i++) {
+		if (r->ranges[i].nx != 0)
+			return (0);
+	}
+	return (1);
+}
+
+/* Ensure we have space for at least n ranges. */
+void
+server_client_ensure_ranges(struct visible_ranges *r, u_int n)
+{
+	if (r->size >= n)
+		return;
+	r->ranges = xrecallocarray(r->ranges, r->size, n, sizeof *r->ranges);
+	r->size = n;
+}
+
 /*
  * Given overlay position and dimensions, return parts of the input range which
  * are visible.
  */
 void
 server_client_overlay_range(u_int x, u_int y, u_int sx, u_int sy, u_int px,
-    u_int py, u_int nx, struct overlay_ranges *r)
+    u_int py, u_int nx, struct visible_ranges *r)
 {
 	u_int	ox, onx;
 
-	/* Return up to 2 ranges. */
-	r->px[2] = 0;
-	r->nx[2] = 0;
-
 	/* Trivial case of no overlap in the y direction. */
 	if (py < y || py > y + sy - 1) {
-		r->px[0] = px;
-		r->nx[0] = nx;
-		r->px[1] = 0;
-		r->nx[1] = 0;
+		server_client_ensure_ranges(r, 1);
+		r->ranges[0].px = px;
+		r->ranges[0].nx = nx;
+		r->used = 1;
 		return;
 	}
+	server_client_ensure_ranges(r, 2);
 
 	/* Visible bit to the left of the popup. */
 	if (px < x) {
-		r->px[0] = px;
-		r->nx[0] = x - px;
-		if (r->nx[0] > nx)
-			r->nx[0] = nx;
+		r->ranges[0].px = px;
+		r->ranges[0].nx = x - px;
+		if (r->ranges[0].nx > nx)
+			r->ranges[0].nx = nx;
 	} else {
-		r->px[0] = 0;
-		r->nx[0] = 0;
+		r->ranges[0].px = 0;
+		r->ranges[0].nx = 0;
 	}
 
 	/* Visible bit to the right of the popup. */
@@ -205,12 +225,13 @@ server_client_overlay_range(u_int x, u_int y, u_int sx, u_int sy, u_int px,
 		ox = px;
 	onx = px + nx;
 	if (onx > ox) {
-		r->px[1] = ox;
-		r->nx[1] = onx - ox;
+		r->ranges[1].px = ox;
+		r->ranges[1].nx = onx - ox;
 	} else {
-		r->px[1] = 0;
-		r->nx[1] = 0;
+		r->ranges[1].px = 0;
+		r->ranges[1].nx = 0;
 	}
+	r->used = 2;
 }
 
 /* Check if this client is inside this server. */
diff --git a/tmux.h b/tmux.h
index 74447785..545b002f 100644
--- a/tmux.h
+++ b/tmux.h
@@ -929,7 +929,7 @@ struct screen_sel;
 struct screen_titles;
 struct screen {
 	char				*title;
-	char *path;
+	char				*path;
 	struct screen_titles		*titles;
 
 	struct grid			*grid;	  /* grid data */
@@ -1500,6 +1500,19 @@ struct key_event {
 	size_t			 len;
 };
 
+/* Visible range array element. */
+struct visible_range {
+	u_int	px;	/* start */
+	u_int	nx;	/* length */
+};
+
+/* Visible areas not obstructed. */
+struct visible_ranges {
+	struct visible_range	*ranges;  /* dynamically allocated array */
+	u_int			 used;    /* number of entries in ranges */
+	u_int			 size;    /* allocated capacity of ranges */
+};
+
 /* Terminal definition. */
 struct tty_term {
 	char		*name;
@@ -1564,6 +1577,7 @@ struct tty {
 	size_t		 discarded;
 
 	struct termios	 tio;
+	struct visible_ranges r;
 
 	struct grid_cell cell;
 	struct grid_cell last_cell;
@@ -1880,22 +1894,15 @@ struct client_window {
 };
 RB_HEAD(client_windows, client_window);
 
-/* Visible areas not obstructed by overlays. */
-#define OVERLAY_MAX_RANGES 3
-struct overlay_ranges {
-	u_int	px[OVERLAY_MAX_RANGES];
-	u_int	nx[OVERLAY_MAX_RANGES];
-};
-
 /* Client connection. */
 typedef int (*prompt_input_cb)(struct client *, void *, const char *, int);
 typedef void (*prompt_free_cb)(void *);
-typedef void (*overlay_check_cb)(struct client*, void *, u_int, u_int, u_int,
-	    struct overlay_ranges *);
+typedef struct visible_ranges *(*overlay_check_cb)(struct client*, void *,
+    u_int, u_int, u_int);
 typedef struct screen *(*overlay_mode_cb)(struct client *, void *, u_int *,
-	    u_int *);
+    u_int *);
 typedef void (*overlay_draw_cb)(struct client *, void *,
-	    struct screen_redraw_ctx *);
+    struct screen_redraw_ctx *);
 typedef int (*overlay_key_cb)(struct client *, void *, struct key_event *);
 typedef void (*overlay_free_cb)(struct client *, void *);
 typedef void (*overlay_resize_cb)(struct client *, void *);
@@ -2487,6 +2494,8 @@ void	tty_reset(struct tty *);
 void	tty_region_off(struct tty *);
 void	tty_margin_off(struct tty *);
 void	tty_cursor(struct tty *, u_int, u_int);
+int	tty_fake_bce(const struct tty *, const struct grid_cell *, u_int);
+void	tty_repeat_space(struct tty *, u_int);
 void	tty_clipboard_query(struct tty *);
 void	tty_putcode(struct tty *, enum tty_code_code);
 void	tty_putcode_i(struct tty *, enum tty_code_code, int);
@@ -2511,7 +2520,15 @@ void	tty_repeat_requests(struct tty *, int);
 void	tty_stop_tty(struct tty *);
 void	tty_set_title(struct tty *, const char *);
 void	tty_set_path(struct tty *, const char *);
+void	tty_default_attributes(struct tty *, const struct grid_cell *,
+	    struct colour_palette *, u_int, struct hyperlinks *);
 void	tty_update_mode(struct tty *, int, struct screen *);
+const struct grid_cell *tty_check_codeset(struct tty *,
+	    const struct grid_cell *);
+struct visible_ranges *tty_check_overlay_range(struct tty *, u_int, u_int,
+	    u_int);
+
+/* tty-draw.c */
 void	tty_draw_line(struct tty *, struct screen *, u_int, u_int, u_int,
 	    u_int, u_int, const struct grid_cell *, struct colour_palette *);
 void	tty_sync_start(struct tty *);
@@ -2858,8 +2875,10 @@ void	 server_client_set_overlay(struct client *, u_int, overlay_check_cb,
 	     overlay_mode_cb, overlay_draw_cb, overlay_key_cb,
 	     overlay_free_cb, overlay_resize_cb, void *);
 void	 server_client_clear_overlay(struct client *);
+void	 server_client_ensure_ranges(struct visible_ranges *, u_int);
+int	 server_client_ranges_is_empty(struct visible_ranges *);
 void	 server_client_overlay_range(u_int, u_int, u_int, u_int, u_int, u_int,
-	     u_int, struct overlay_ranges *);
+	     u_int, struct visible_ranges *);
 void	 server_client_set_key_table(struct client *, const char *);
 const char *server_client_get_key_table(struct client *);
 int	 server_client_check_nested(struct client *);
@@ -3171,7 +3190,7 @@ void	 screen_set_selection(struct screen *, u_int, u_int, u_int, u_int,
 void	 screen_clear_selection(struct screen *);
 void	 screen_hide_selection(struct screen *);
 int	 screen_check_selection(struct screen *, u_int, u_int);
-void	 screen_select_cell(struct screen *, struct grid_cell *,
+int	 screen_select_cell(struct screen *, struct grid_cell *,
 	     const struct grid_cell *);
 void	 screen_alternate_on(struct screen *, struct grid_cell *, int);
 void	 screen_alternate_off(struct screen *, struct grid_cell *, int);
@@ -3557,8 +3576,8 @@ int		 menu_display(struct menu *, int, int, struct cmdq_item *,
 		    const char *, const char *, struct cmd_find_state *,
 		    menu_choice_cb, void *);
 struct screen	*menu_mode_cb(struct client *, void *, u_int *, u_int *);
-void		 menu_check_cb(struct client *, void *, u_int, u_int, u_int,
-		    struct overlay_ranges *);
+struct visible_ranges *menu_check_cb(struct client *, void *, u_int, u_int,
+		    u_int);
 void		 menu_draw_cb(struct client *, void *,
 		    struct screen_redraw_ctx *);
 void		 menu_free_cb(struct client *, void *);
diff --git a/tty-draw.c b/tty-draw.c
new file mode 100644
index 00000000..eac92a8f
--- /dev/null
+++ b/tty-draw.c
@@ -0,0 +1,319 @@
+/* $OpenBSD$ */
+
+/*
+ * Copyright (c) 2026 Nicholas Marriott <nicholas.marriott@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <string.h>
+
+#include "tmux.h"
+
+enum tty_draw_line_state {
+	TTY_DRAW_LINE_FIRST,
+	TTY_DRAW_LINE_FLUSH,
+	TTY_DRAW_LINE_NEW1,
+	TTY_DRAW_LINE_NEW2,
+	TTY_DRAW_LINE_EMPTY,
+	TTY_DRAW_LINE_SAME,
+	TTY_DRAW_LINE_PAD,
+	TTY_DRAW_LINE_DONE
+};
+static const char* tty_draw_line_states[] = {
+	"FIRST",
+	"FLUSH",
+	"NEW1",
+	"NEW2",
+	"EMPTY",
+	"SAME",
+	"PAD",
+	"DONE"
+};
+
+/* Clear part of the line. */
+static void
+tty_draw_line_clear(struct tty *tty, u_int px, u_int py, u_int nx,
+    const struct grid_cell *defaults, u_int bg, int wrapped)
+{
+	/* Nothing to clear. */
+	if (nx == 0)
+		return;
+
+	/* If genuine BCE is available, can try escape sequences. */
+	if (!wrapped && nx >= 10 && !tty_fake_bce(tty, defaults, bg)) {
+		/* Off the end of the line, use EL if available. */
+		if (px + nx >= tty->sx && tty_term_has(tty->term, TTYC_EL)) {
+			tty_cursor(tty, px, py);
+			tty_putcode(tty, TTYC_EL);
+			return;
+		}
+
+		/* At the start of the line. Use EL1. */
+		if (px == 0 && tty_term_has(tty->term, TTYC_EL1)) {
+			tty_cursor(tty, px + nx - 1, py);
+			tty_putcode(tty, TTYC_EL1);
+			return;
+		}
+
+		/* Section of line. Use ECH if possible. */
+		if (tty_term_has(tty->term, TTYC_ECH)) {
+			tty_cursor(tty, px, py);
+			tty_putcode_i(tty, TTYC_ECH, nx);
+			return;
+		}
+	}
+
+        /* Couldn't use an escape sequence, use spaces. */
+	if (px != 0 || !wrapped)
+		tty_cursor(tty, px, py);
+	if (nx == 1)
+		tty_putc(tty, ' ');
+	else if (nx == 2)
+		tty_putn(tty, "  ", 2, 2);
+	else
+		tty_repeat_space(tty, nx);
+}
+
+/* Is this cell empty? */
+static u_int
+tty_draw_line_get_empty(const struct grid_cell *gc, u_int nx)
+{
+	u_int	empty = 0;
+
+	if (gc->data.width != 1 && gc->data.width > nx)
+		empty = nx;
+	else if (gc->attr == 0 && gc->link == 0) {
+		if (gc->flags & GRID_FLAG_CLEARED)
+			empty = 1;
+		else if (gc->flags & GRID_FLAG_TAB)
+			empty = gc->data.width;
+		else if (gc->data.size == 1 && *gc->data.data == ' ')
+			empty = 1;
+	}
+	return (empty);
+}
+
+/* Draw a line from screen to tty. */
+void
+tty_draw_line(struct tty *tty, struct screen *s, u_int px, u_int py, u_int nx,
+    u_int atx, u_int aty, const struct grid_cell *defaults,
+    struct colour_palette *palette)
+{
+	struct grid		*gd = s->grid;
+	const struct grid_cell	*gcp;
+	struct grid_cell	 gc, ngc, last;
+	struct grid_line	*gl;
+	u_int			 i, j, last_i, cx, ex, width;
+	u_int			 cellsize, bg;
+	int			 flags, empty, wrapped = 0;
+	char			 buf[1000];
+	size_t			 len;
+	enum tty_draw_line_state current_state, next_state;
+
+	/*
+	 * py is the line in the screen to draw. px is the start x and nx is
+	 * the width to draw. atx,aty is the line on the terminal to draw it.
+	 */
+	log_debug("%s: px=%u py=%u nx=%u atx=%u aty=%u", __func__, px, py, nx,
+	    atx, aty);
+
+	/*
+	 * Clamp the width to cellsize - note this is not cellused, because
+	 * there may be empty background cells after it (from BCE).
+	 */
+	cellsize = grid_get_line(gd, gd->hsize + py)->cellsize;
+	if (screen_size_x(s) > cellsize)
+		ex = cellsize;
+	else {
+		ex = screen_size_x(s);
+		if (px > ex)
+			return;
+		if (px + nx > ex)
+			nx = ex - px;
+	}
+	if (ex < nx)
+		ex = nx;
+	log_debug("%s: drawing %u-%u,%u (end %u) at %u,%u; defaults: fg=%d, "
+	    "bg=%d", __func__, px, px + nx, py, ex, atx, aty, defaults->fg,
+	    defaults->bg);
+
+	/*
+	 * If there is padding at the start, we must have truncated a wide
+	 * character. Clear it.
+	 */
+	cx = 0;
+	for (i = px; i < px + nx; i++) {
+		grid_view_get_cell(gd, i, py, &gc);
+		if (~gc.flags & GRID_FLAG_PADDING)
+			break;
+		cx++;
+	}
+	if (cx != 0) {
+		/* Find the previous cell for the background colour. */
+		for (i = px + 1; i > 0; i--) {
+			grid_view_get_cell(gd, i - 1, py, &gc);
+			if (~gc.flags & GRID_FLAG_PADDING)
+				break;
+		}
+		if (i == 0)
+			bg = defaults->bg;
+		else {
+			bg = gc.bg;
+			if (gc.flags & GRID_FLAG_SELECTED) {
+				memcpy(&ngc, &gc, sizeof ngc);
+				if (screen_select_cell(s, &ngc, &gc))
+					bg = ngc.bg;
+			}
+		}
+		tty_attributes(tty, &last, defaults, palette, s->hyperlinks);
+		log_debug("%s: clearing %u padding cells", __func__, cx);
+		tty_draw_line_clear(tty, atx, aty, cx, defaults, bg, 0);
+		if (cx == ex)
+			return;
+		atx += cx;
+		px += cx;
+		nx -= cx;
+		ex -= cx;
+	}
+
+	/* Did the previous line wrap on to this one? */
+	if (py != 0 && atx == 0 && tty->cx >= tty->sx && nx == tty->sx) {
+		gl = grid_get_line(gd, gd->hsize + py - 1);
+		if (gl->flags & GRID_LINE_WRAPPED)
+			wrapped = 1;
+	}
+
+	/* Turn off cursor while redrawing and reset region and margins. */
+	flags = (tty->flags & TTY_NOCURSOR);
+	tty->flags |= TTY_NOCURSOR;
+	tty_update_mode(tty, tty->mode, s);
+	tty_region_off(tty);
+	tty_margin_off(tty);
+
+	/* Start with the default cell as the last cell. */
+	memcpy(&last, &grid_default_cell, sizeof last);
+	last.bg = defaults->bg;
+	tty_default_attributes(tty, defaults, palette, 8, s->hyperlinks);
+
+	/* Loop over each character in the range. */
+	last_i = i = 0;
+	len = 0;
+	width = 0;
+	current_state = TTY_DRAW_LINE_FIRST;
+	for (;;) {
+		/* Work out the next state. */
+		if (i == nx) {
+			/*
+			 * If this is the last cell, we are done. But we need to
+			 * go through the loop again to flush anything in
+			 * the buffer.
+			 */
+			empty = 0;
+			next_state = TTY_DRAW_LINE_DONE;
+		} else {
+			/* Get the current cell. */
+			grid_view_get_cell(gd, px + i, py, &gc);
+
+			/* Update for codeset if needed. */
+			gcp = tty_check_codeset(tty, &gc);
+
+			/* And for selection. */
+			if (gcp->flags & GRID_FLAG_SELECTED) {
+				memcpy(&ngc, gcp, sizeof ngc);
+				if (screen_select_cell(s, &ngc, gcp))
+					gcp = &ngc;
+			}
+
+			/* Work out the the empty width. */
+			if (i >= ex)
+				empty = 1;
+			else
+				empty = tty_draw_line_get_empty(gcp, nx - i);
+
+			/* Work out the next state. */
+			if (empty != 0)
+				next_state = TTY_DRAW_LINE_EMPTY;
+			else if (current_state == TTY_DRAW_LINE_FIRST)
+				next_state = TTY_DRAW_LINE_SAME;
+			else if (gcp->flags & GRID_FLAG_PADDING)
+				next_state = TTY_DRAW_LINE_PAD;
+			else if (grid_cells_look_equal(gcp, &last)) {
+				if (gcp->data.size > (sizeof buf) - len)
+					next_state = TTY_DRAW_LINE_FLUSH;
+				else
+					next_state = TTY_DRAW_LINE_SAME;
+			} else if (current_state == TTY_DRAW_LINE_NEW1)
+				next_state = TTY_DRAW_LINE_NEW2;
+			else
+				next_state = TTY_DRAW_LINE_NEW1;
+		}
+		log_debug("%s: cell %u empty %u, bg %u; state: current %s, "
+		    "next %s", __func__, px + i, empty, gcp->bg,
+		    tty_draw_line_states[current_state],
+		    tty_draw_line_states[next_state]);
+
+		/* If the state has changed, flush any collected data. */
+		if (next_state != current_state) {
+			if (current_state == TTY_DRAW_LINE_EMPTY) {
+				tty_attributes(tty, &last, defaults, palette,
+				    s->hyperlinks);
+				tty_draw_line_clear(tty, atx + last_i, aty,
+				    i - last_i, defaults, last.bg, wrapped);
+				wrapped = 0;
+			} else if (next_state != TTY_DRAW_LINE_SAME &&
+			    len != 0) {
+				tty_attributes(tty, &last, defaults, palette,
+				    s->hyperlinks);
+				if (atx + i - width != 0 || !wrapped)
+					tty_cursor(tty, atx + i - width, aty);
+				if (~last.attr & GRID_ATTR_CHARSET)
+					tty_putn(tty, buf, len, width);
+				else {
+					for (j = 0; j < len; j++)
+						tty_putc(tty, buf[j]);
+				}
+				len = 0;
+				width = 0;
+				wrapped = 0;
+			}
+			last_i = i;
+		}
+
+		/* Append the cell if it is not empty and not padding. */
+		if (next_state != TTY_DRAW_LINE_EMPTY &&
+		    next_state != TTY_DRAW_LINE_PAD) {
+			memcpy(buf + len, gcp->data.data, gcp->data.size);
+			len += gcp->data.size;
+			width += gcp->data.width;
+		}
+
+		/* If this is the last cell, we are done. */
+		if (next_state == TTY_DRAW_LINE_DONE)
+			break;
+
+		/* Otherwise move to the next. */
+		current_state = next_state;
+		memcpy(&last, gcp, sizeof last);
+		if (empty != 0)
+			i += empty;
+		else
+			i += gcp->data.width;
+	}
+
+	tty->flags = (tty->flags & ~TTY_NOCURSOR)|flags;
+	tty_update_mode(tty, tty->mode, s);
+}
+
diff --git a/tty.c b/tty.c
index 8b670b3f..6e413572 100644
--- a/tty.c
+++ b/tty.c
@@ -61,18 +61,11 @@ static void	tty_region(struct tty *, u_int, u_int);
 static void	tty_margin_pane(struct tty *, const struct tty_ctx *);
 static void	tty_margin(struct tty *, u_int, u_int);
 static int	tty_large_region(struct tty *, const struct tty_ctx *);
-static int	tty_fake_bce(const struct tty *, const struct grid_cell *,
-		    u_int);
 static void	tty_redraw_region(struct tty *, const struct tty_ctx *);
 static void	tty_emulate_repeat(struct tty *, enum tty_code_code,
 		    enum tty_code_code, u_int);
-static void	tty_repeat_space(struct tty *, u_int);
 static void	tty_draw_pane(struct tty *, const struct tty_ctx *, u_int);
-static void	tty_default_attributes(struct tty *, const struct grid_cell *,
-		    struct colour_palette *, u_int, struct hyperlinks *);
 static int	tty_check_overlay(struct tty *, u_int, u_int);
-static void	tty_check_overlay_range(struct tty *, u_int, u_int, u_int,
-		    struct overlay_ranges *);
 
 #define tty_use_margin(tty) \
 	(tty->term->flags & TERM_DECSLRM)
@@ -523,6 +516,8 @@ void
 tty_free(struct tty *tty)
 {
 	tty_close(tty);
+
+	free(tty->r.ranges);
 }
 
 void
@@ -907,7 +902,7 @@ tty_emulate_repeat(struct tty *tty, enum tty_code_code code,
 	}
 }
 
-static void
+void
 tty_repeat_space(struct tty *tty, u_int n)
 {
 	static char s[500];
@@ -1066,7 +1061,7 @@ tty_large_region(__unused struct tty *tty, const struct tty_ctx *ctx)
  * Return if BCE is needed but the terminal doesn't have it - it'll need to be
  * emulated.
  */
-static int
+int
 tty_fake_bce(const struct tty *tty, const struct grid_cell *gc, u_int bg)
 {
 	if (tty_term_flag(tty->term, TTYC_BCE))
@@ -1161,8 +1156,6 @@ tty_clear_line(struct tty *tty, const struct grid_cell *defaults, u_int py,
     u_int px, u_int nx, u_int bg)
 {
 	struct client		*c = tty->client;
-	struct overlay_ranges	 r;
-	u_int			 i;
 
 	log_debug("%s: %s, %u at %u,%u", __func__, c->name, nx, px, py);
 
@@ -1198,13 +1191,8 @@ tty_clear_line(struct tty *tty, const struct grid_cell *defaults, u_int py,
 	 * Couldn't use an escape sequence, use spaces. Clear only the visible
 	 * bit if there is an overlay.
 	 */
-	tty_check_overlay_range(tty, px, py, nx, &r);
-	for (i = 0; i < OVERLAY_MAX_RANGES; i++) {
-		if (r.nx[i] == 0)
-			continue;
-		tty_cursor(tty, r.px[i], py);
-		tty_repeat_space(tty, r.nx[i]);
-	}
+	tty_cursor(tty, px, py);
+	tty_repeat_space(tty, nx);
 }
 
 /* Clear a line, adjusting to visible part of pane. */
@@ -1385,7 +1373,7 @@ tty_draw_pane(struct tty *tty, const struct tty_ctx *ctx, u_int py)
 	}
 }
 
-static const struct grid_cell *
+const struct grid_cell *
 tty_check_codeset(struct tty *tty, const struct grid_cell *gc)
 {
 	static struct grid_cell	new;
@@ -1418,229 +1406,34 @@ tty_check_codeset(struct tty *tty, const struct grid_cell *gc)
 	return (&new);
 }
 
-/*
- * Check if a single character is obstructed by the overlay and return a
- * boolean.
- */
+/* Check if a single character is covered by the overlay. */
 static int
 tty_check_overlay(struct tty *tty, u_int px, u_int py)
 {
-	struct overlay_ranges	r;
+	struct visible_ranges	*r;
 
 	/*
-	 * A unit width range will always return nx[2] == 0 from a check, even
-	 * with multiple overlays, so it's sufficient to check just the first
-	 * two entries.
+	 * With a single character, if there is anything visible (that is, the
+	 * range is not empty), it must be that character.
 	 */
-	tty_check_overlay_range(tty, px, py, 1, &r);
-	if (r.nx[0] + r.nx[1] == 0)
-		return (0);
-	return (1);
+	r = tty_check_overlay_range(tty, px, py, 1);
+	return (!server_client_ranges_is_empty(r));
 }
 
 /* Return parts of the input range which are visible. */
-static void
-tty_check_overlay_range(struct tty *tty, u_int px, u_int py, u_int nx,
-    struct overlay_ranges *r)
+struct visible_ranges *
+tty_check_overlay_range(struct tty *tty, u_int px, u_int py, u_int nx)
 {
 	struct client	*c = tty->client;
 
 	if (c->overlay_check == NULL) {
-		r->px[0] = px;
-		r->nx[0] = nx;
-		r->px[1] = 0;
-		r->nx[1] = 0;
-		r->px[2] = 0;
-		r->nx[2] = 0;
-		return;
+		server_client_ensure_ranges(&tty->r, 1);
+		tty->r.ranges[0].px = px;
+		tty->r.ranges[0].nx = nx;
+		tty->r.used = 1;
+		return (&tty->r);
 	}
-
-	c->overlay_check(c, c->overlay_data, px, py, nx, r);
-}
-
-void
-tty_draw_line(struct tty *tty, struct screen *s, u_int px, u_int py, u_int nx,
-    u_int atx, u_int aty, const struct grid_cell *defaults,
-    struct colour_palette *palette)
-{
-	struct grid		*gd = s->grid;
-	struct grid_cell	 gc, last;
-	const struct grid_cell	*gcp;
-	struct grid_line	*gl;
-	struct client		*c = tty->client;
-	struct overlay_ranges	 r;
-	u_int			 i, j, ux, sx, width, hidden, eux, nxx;
-	u_int			 cellsize;
-	int			 flags, cleared = 0, wrapped = 0;
-	char			 buf[512];
-	size_t			 len;
-
-	log_debug("%s: px=%u py=%u nx=%u atx=%u aty=%u", __func__,
-	    px, py, nx, atx, aty);
-	log_debug("%s: defaults: fg=%d, bg=%d", __func__, defaults->fg,
-	    defaults->bg);
-
-	/*
-	 * py is the line in the screen to draw.
-	 * px is the start x and nx is the width to draw.
-	 * atx,aty is the line on the terminal to draw it.
-	 */
-
-	flags = (tty->flags & TTY_NOCURSOR);
-	tty->flags |= TTY_NOCURSOR;
-	tty_update_mode(tty, tty->mode, s);
-
-	tty_region_off(tty);
-	tty_margin_off(tty);
-
-	/*
-	 * Clamp the width to cellsize - note this is not cellused, because
-	 * there may be empty background cells after it (from BCE).
-	 */
-	sx = screen_size_x(s);
-	if (nx > sx)
-		nx = sx;
-	cellsize = grid_get_line(gd, gd->hsize + py)->cellsize;
-	if (sx > cellsize)
-		sx = cellsize;
-	if (sx > tty->sx)
-		sx = tty->sx;
-	if (sx > nx)
-		sx = nx;
-	ux = 0;
-
-	if (py == 0)
-		gl = NULL;
-	else
-		gl = grid_get_line(gd, gd->hsize + py - 1);
-	if (gl == NULL ||
-	    (~gl->flags & GRID_LINE_WRAPPED) ||
-	    atx != 0 ||
-	    tty->cx < tty->sx ||
-	    nx < tty->sx) {
-		if (nx < tty->sx &&
-		    atx == 0 &&
-		    px + sx != nx &&
-		    tty_term_has(tty->term, TTYC_EL1) &&
-		    !tty_fake_bce(tty, defaults, 8) &&
-		    c->overlay_check == NULL) {
-			tty_default_attributes(tty, defaults, palette, 8,
-			    s->hyperlinks);
-			tty_cursor(tty, nx - 1, aty);
-			tty_putcode(tty, TTYC_EL1);
-			cleared = 1;
-		}
-	} else {
-		log_debug("%s: wrapped line %u", __func__, aty);
-		wrapped = 1;
-	}
-
-	memcpy(&last, &grid_default_cell, sizeof last);
-	len = 0;
-	width = 0;
-
-	for (i = 0; i < sx; i++) {
-		grid_view_get_cell(gd, px + i, py, &gc);
-		gcp = tty_check_codeset(tty, &gc);
-		if (len != 0 &&
-		    (!tty_check_overlay(tty, atx + ux + width, aty) ||
-		    (gcp->attr & GRID_ATTR_CHARSET) ||
-		    gcp->flags != last.flags ||
-		    gcp->attr != last.attr ||
-		    gcp->fg != last.fg ||
-		    gcp->bg != last.bg ||
-		    gcp->us != last.us ||
-		    gcp->link != last.link ||
-		    ux + width + gcp->data.width > nx ||
-		    (sizeof buf) - len < gcp->data.size)) {
-			tty_attributes(tty, &last, defaults, palette,
-			    s->hyperlinks);
-			if (last.flags & GRID_FLAG_CLEARED) {
-				log_debug("%s: %zu cleared", __func__, len);
-				tty_clear_line(tty, defaults, aty, atx + ux,
-				    width, last.bg);
-			} else {
-				if (!wrapped || atx != 0 || ux != 0)
-					tty_cursor(tty, atx + ux, aty);
-				tty_putn(tty, buf, len, width);
-			}
-			ux += width;
-
-			len = 0;
-			width = 0;
-			wrapped = 0;
-		}
-
-		if (gcp->flags & GRID_FLAG_SELECTED)
-			screen_select_cell(s, &last, gcp);
-		else
-			memcpy(&last, gcp, sizeof last);
-
-		tty_check_overlay_range(tty, atx + ux, aty, gcp->data.width,
-		    &r);
-		hidden = 0;
-		for (j = 0; j < OVERLAY_MAX_RANGES; j++)
-			hidden += r.nx[j];
-		hidden = gcp->data.width - hidden;
-		if (hidden != 0 && hidden == gcp->data.width) {
-			if (~gcp->flags & GRID_FLAG_PADDING)
-				ux += gcp->data.width;
-		} else if (hidden != 0 || ux + gcp->data.width > nx) {
-			if (~gcp->flags & GRID_FLAG_PADDING) {
-				tty_attributes(tty, &last, defaults, palette,
-				    s->hyperlinks);
-				for (j = 0; j < OVERLAY_MAX_RANGES; j++) {
-					if (r.nx[j] == 0)
-						continue;
-					/* Effective width drawn so far. */
-					eux = r.px[j] - atx;
-					if (eux < nx) {
-						tty_cursor(tty, r.px[j], aty);
-						nxx = nx - eux;
-						if (r.nx[j] > nxx)
-							r.nx[j] = nxx;
-						tty_repeat_space(tty, r.nx[j]);
-						ux = eux + r.nx[j];
-					}
-				}
-			}
-		} else if (gcp->attr & GRID_ATTR_CHARSET) {
-			tty_attributes(tty, &last, defaults, palette,
-			    s->hyperlinks);
-			tty_cursor(tty, atx + ux, aty);
-			for (j = 0; j < gcp->data.size; j++)
-				tty_putc(tty, gcp->data.data[j]);
-			ux += gcp->data.width;
-		} else if (~gcp->flags & GRID_FLAG_PADDING) {
-			memcpy(buf + len, gcp->data.data, gcp->data.size);
-			len += gcp->data.size;
-			width += gcp->data.width;
-		}
-	}
-	if (len != 0 && ((~last.flags & GRID_FLAG_CLEARED) || last.bg != 8)) {
-		tty_attributes(tty, &last, defaults, palette, s->hyperlinks);
-		if (last.flags & GRID_FLAG_CLEARED) {
-			log_debug("%s: %zu cleared (end)", __func__, len);
-			tty_clear_line(tty, defaults, aty, atx + ux, width,
-			    last.bg);
-		} else {
-			if (!wrapped || atx != 0 || ux != 0)
-				tty_cursor(tty, atx + ux, aty);
-			tty_putn(tty, buf, len, width);
-		}
-		ux += width;
-	}
-
-	if (!cleared && ux < nx) {
-		log_debug("%s: %u to end of line (%zu cleared)", __func__,
-		    nx - ux, len);
-		tty_default_attributes(tty, defaults, palette, 8,
-		    s->hyperlinks);
-		tty_clear_line(tty, defaults, aty, atx + ux, nx - ux, 8);
-	}
-
-	tty->flags = (tty->flags & ~TTY_NOCURSOR) | flags;
-	tty_update_mode(tty, tty->mode, s);
+	return (c->overlay_check(c, c->overlay_data, px, py, nx));
 }
 
 void
@@ -2103,7 +1896,7 @@ tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
 {
 	const struct grid_cell	*gcp = ctx->cell;
 	struct screen		*s = ctx->s;
-	struct overlay_ranges	 r;
+	struct visible_ranges	*r;
 	u_int			 px, py, i, vis = 0;
 
 	px = ctx->xoff + ctx->ocx - ctx->wox;
@@ -2120,9 +1913,9 @@ tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
 
 	/* Handle partially obstructed wide characters. */
 	if (gcp->data.width > 1) {
-		tty_check_overlay_range(tty, px, py, gcp->data.width, &r);
-		for (i = 0; i < OVERLAY_MAX_RANGES; i++)
-			vis += r.nx[i];
+		r = tty_check_overlay_range(tty, px, py, gcp->data.width);
+		for (i = 0; i < r->used; i++)
+			vis += r->ranges[i].nx;
 		if (vis < gcp->data.width) {
 			tty_draw_line(tty, s, s->cx, s->cy, gcp->data.width,
 			    px, py, &ctx->defaults, ctx->palette);
@@ -2148,7 +1941,8 @@ tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
 void
 tty_cmd_cells(struct tty *tty, const struct tty_ctx *ctx)
 {
-	struct overlay_ranges	 r;
+	struct visible_ranges	*r;
+	struct visible_range	*rr;
 	u_int			 i, px, py, cx;
 	char			*cp = ctx->ptr;
 
@@ -2173,20 +1967,21 @@ tty_cmd_cells(struct tty *tty, const struct tty_ctx *ctx)
 
 	tty_margin_off(tty);
 	tty_cursor_pane_unless_wrap(tty, ctx, ctx->ocx, ctx->ocy);
-	tty_attributes(tty, ctx->cell, &ctx->defaults, ctx->palette, ctx->s->hyperlinks);
+	tty_attributes(tty, ctx->cell, &ctx->defaults, ctx->palette,
+	    ctx->s->hyperlinks);
 
 	/* Get tty position from pane position for overlay check. */
 	px = ctx->xoff + ctx->ocx - ctx->wox;
 	py = ctx->yoff + ctx->ocy - ctx->woy;
 
-	tty_check_overlay_range(tty, px, py, ctx->num, &r);
-	for (i = 0; i < OVERLAY_MAX_RANGES; i++) {
-		if (r.nx[i] == 0)
-			continue;
-		/* Convert back to pane position for printing. */
-		cx = r.px[i] - ctx->xoff + ctx->wox;
-		tty_cursor_pane_unless_wrap(tty, ctx, cx, ctx->ocy);
-		tty_putn(tty, cp + r.px[i] - px, r.nx[i], r.nx[i]);
+	r = tty_check_overlay_range(tty, px, py, ctx->num);
+	for (i = 0; i < r->used; i++) {
+		rr = &r->ranges[i];
+		if (rr->nx != 0) {
+			cx = rr->px - ctx->xoff + ctx->wox;
+			tty_cursor_pane_unless_wrap(tty, ctx, cx, ctx->ocy);
+			tty_putn(tty, cp + rr->px - px, rr->nx, rr->nx);
+		}
 	}
 }
 
@@ -3081,7 +2876,7 @@ tty_default_colours(struct grid_cell *gc, struct window_pane *wp)
 	}
 }
 
-static void
+void
 tty_default_attributes(struct tty *tty, const struct grid_cell *defaults,
     struct colour_palette *palette, u_int bg, struct hyperlinks *hl)
 {