From 44b8a40b8c8dea2fb938b38263844986b1deb6d1 Mon Sep 17 00:00:00 2001
From: nicm <nicm@openbsd.org>
Date: Wed, 29 Jul 2026 17:42:56 +0000
Subject: [PATCH] Correctly skip padding at end of line, GitHub issue 5411.

---
 grid-reader.c |  9 +++------
 grid.c        | 22 +++++++++++++++++++++-
 tmux.h        |  3 ++-
 window-copy.c | 11 ++++-------
 4 files changed, 30 insertions(+), 15 deletions(-)

diff --git a/grid-reader.c b/grid-reader.c
index 9b40def6c..4cf47b8cb 100644
--- a/grid-reader.c
+++ b/grid-reader.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: grid-reader.c,v 1.10 2026/05/17 13:12:21 nicm Exp $ */
+/* $OpenBSD: grid-reader.c,v 1.11 2026/07/29 17:42:56 nicm Exp $ */
 
 /*
  * Copyright (c) 2020 Anindya Mukherjee <anindya49@hotmail.com>
@@ -54,11 +54,8 @@ grid_reader_cursor_right(struct grid_reader *gr, int wrap, int all, int onemore)
 		px = gr->gd->sx;
 	else if (onemore)
 		px = grid_reader_line_length(gr);
-	else {
-		px = grid_reader_line_length(gr);
-		if (px != 0)
-			px--;
-	}
+	else
+		px = grid_line_limit(gr->gd, gr->cy);
 
 	if (wrap && gr->cx >= px && gr->cy < gr->gd->hsize + gr->gd->sy - 1) {
 		grid_reader_cursor_start_of_line(gr, 0);
diff --git a/grid.c b/grid.c
index fa0c94ffe..4e837f108 100644
--- a/grid.c
+++ b/grid.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: grid.c,v 1.154 2026/07/20 11:16:33 nicm Exp $ */
+/* $OpenBSD: grid.c,v 1.155 2026/07/29 17:42:56 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1630,6 +1630,26 @@ grid_line_length(struct grid *gd, u_int py)
 	return (px);
 }
 
+/* Get last position on line, not including padding. */
+u_int
+grid_line_limit(struct grid *gd, u_int py)
+{
+	struct grid_cell	gc;
+	u_int			px;
+
+	px = grid_line_length(gd, py);
+	if (px == 0)
+		return (0);
+	px--;
+	while (px > 0) {
+		grid_get_cell(gd, px, py, &gc);
+		if (~gc.flags & GRID_FLAG_PADDING)
+			break;
+		px--;
+	}
+	return (px);
+}
+
 /* Check if character is in set. */
 int
 grid_in_set(struct grid *gd, u_int px, u_int py, const char *set)
diff --git a/tmux.h b/tmux.h
index 4ac613711..ca5df3826 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: tmux.h,v 1.1417 2026/07/29 14:06:32 nicm Exp $ */
+/* $OpenBSD: tmux.h,v 1.1418 2026/07/29 17:42:56 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -3464,6 +3464,7 @@ void	 grid_reflow(struct grid *, u_int);
 void	 grid_wrap_position(struct grid *, u_int, u_int, u_int *, u_int *);
 void	 grid_unwrap_position(struct grid *, u_int *, u_int *, u_int, u_int);
 u_int	 grid_line_length(struct grid *, u_int);
+u_int	 grid_line_limit(struct grid *, u_int);
 int	 grid_in_set(struct grid *, u_int, u_int, const char *);
 
 /* grid-reader.c */
diff --git a/window-copy.c b/window-copy.c
index ff58dfbad..dabb2a99c 100644
--- a/window-copy.c
+++ b/window-copy.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: window-copy.c,v 1.423 2026/07/21 11:52:13 nicm Exp $ */
+/* $OpenBSD: window-copy.c,v 1.424 2026/07/29 17:42:56 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -6215,16 +6215,13 @@ static u_int
 window_copy_cursor_limit(struct window_mode_entry *wme, u_int py,
     int allow_onemore)
 {
+	struct window_copy_mode_data	*data = wme->data;
 	struct options			*oo = wme->wp->window->options;
-	u_int				 len;
 
-	len = window_copy_find_length(wme, py);
 	if (allow_onemore ||
 	    options_get_number(oo, "mode-keys") != MODEKEY_VI)
-		return (len);
-	if (len == 0)
-		return (0);
-	return (len - 1);
+		return (window_copy_find_length(wme, py));
+	return (grid_line_limit(data->backing->grid, py));
 }
 
 static void