Fix resizing floating pane with a left scrollbar, from Michael Grant.

usr.bin/tmux/cmd-resize-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: cmd-resize-pane.c,v 1.58 2026/06/14 19:31:37 nicm Exp $ */
+/* $OpenBSD: cmd-resize-pane.c,v 1.59 2026/06/16 08:57:07 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -226,6 +226,7 @@ cmd_resize_pane_mouse_update_floating(struct client *c, struct mouse_event *m)
 	struct window_pane	*wp;
 	struct layout_cell	*lc;
 	int			 y, ly, x, lx, sx, sy, new_sx, new_sy;
+	int			 scrollbars, sb_pos, left, right;
 	int			 new_xoff, new_yoff, resizes = 0;
 
 	wp = cmd_mouse_pane(m, NULL, &wl);
@@ -237,6 +238,17 @@ cmd_resize_pane_mouse_update_floating(struct client *c, struct mouse_event *m)
 	lc = wp->layout_cell;
 	sx = wp->sx;
 	sy = wp->sy;
+	scrollbars = options_get_number(w->options, "pane-scrollbars");
+	sb_pos = options_get_number(w->options, "pane-scrollbars-position");
+	left = wp->xoff - 1;
+	right = wp->xoff + sx;
+	if (window_pane_show_scrollbar(wp, scrollbars) &&
+	    sb_pos == PANE_SCROLLBARS_LEFT) {
+		left -= wp->scrollbar_style.width + wp->scrollbar_style.pad;
+	} else if (window_pane_show_scrollbar(wp, scrollbars) &&
+	    sb_pos == PANE_SCROLLBARS_RIGHT) {
+		right += wp->scrollbar_style.width + wp->scrollbar_style.pad;
+	}
 
 	y = m->y + m->oy; x = m->x + m->ox;
 	if (m->statusat == 0 && y >= (int)m->statuslines)
@@ -249,7 +261,7 @@ cmd_resize_pane_mouse_update_floating(struct client *c, struct mouse_event *m)
 	else if (m->statusat > 0 && ly >= m->statusat)
 		ly = m->statusat - 1;
 
-	if ((lx == wp->xoff - 1 || lx == wp->xoff) && ly == wp->yoff - 1) {
+	if ((lx == left || lx == left + 1) && ly == wp->yoff - 1) {
 		/* Top left corner. */
 		new_sx = lc->sx + (lx - x);
 		if (new_sx < PANE_MINIMUM)
@@ -261,7 +273,7 @@ cmd_resize_pane_mouse_update_floating(struct client *c, struct mouse_event *m)
 		new_yoff = y + 1;
 		layout_set_size(lc, new_sx, new_sy, new_xoff, new_yoff);
 		resizes++;
-	} else if ((lx == wp->xoff + sx + 1 || lx == wp->xoff + sx) &&
+	} else if ((lx == right + 1 || lx == right) &&
 	    ly == wp->yoff - 1) {
 		/* Top right corner. */
 		new_sx = x - lc->xoff;
@@ -273,7 +285,7 @@ cmd_resize_pane_mouse_update_floating(struct client *c, struct mouse_event *m)
 		new_yoff = y + 1;
 		layout_set_size(lc, new_sx, new_sy, lc->xoff, new_yoff);
 		resizes++;
-	} else if ((lx == wp->xoff - 1 || lx == wp->xoff) &&
+	} else if ((lx == left || lx == left + 1) &&
 	    ly == wp->yoff + sy) {
 		/* Bottom left corner. */
 		new_sx = lc->sx + (lx - x);
@@ -285,7 +297,7 @@ cmd_resize_pane_mouse_update_floating(struct client *c, struct mouse_event *m)
 		new_xoff = x + 1;
 		layout_set_size(lc, new_sx, new_sy, new_xoff, lc->yoff);
 		resizes++;
-	} else if ((lx == wp->xoff + sx + 1 || lx == wp->xoff + sx) &&
+	} else if ((lx == right + 1 || lx == right) &&
 	    ly == wp->yoff + sy) {
 		/* Bottom right corner. */
 		new_sx = x - lc->xoff;
@@ -296,14 +308,14 @@ cmd_resize_pane_mouse_update_floating(struct client *c, struct mouse_event *m)
 			new_sy = PANE_MINIMUM;
 		layout_set_size(lc, new_sx, new_sy, lc->xoff, lc->yoff);
 		resizes++;
-	} else if (lx == wp->xoff + sx + 1) {
+	} else if (lx == right) {
 		/* Right border. */
 		new_sx = x - lc->xoff;
 		if (new_sx < PANE_MINIMUM)
 			return;
 		layout_set_size(lc, new_sx, lc->sy, lc->xoff, lc->yoff);
 		resizes++;
-	} else if (lx == wp->xoff - 1) {
+	} else if (lx == left) {
 		/* Left border. */
 		new_sx = lc->sx + (lx - x);
 		if (new_sx < PANE_MINIMUM)

usr.bin/tmux/server-client.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: server-client.c,v 1.471 2026/06/15 17:34:25 nicm Exp $ */
+/* $OpenBSD: server-client.c,v 1.472 2026/06/16 08:57:07 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -631,6 +631,9 @@ server_client_check_mouse_in_pane(struct window_pane *wp, int px, int py,
 		pane_status_line = wp->yoff + wp->sy;
 	else
 		pane_status_line = -1; /* not used */
+	bdr_left = wp->xoff - 1;
+	if (sb_pos == PANE_SCROLLBARS_LEFT)
+		bdr_left -= sb_pad + sb_w;
 
 	/* Check if point is within the pane or scrollbar. */
 	if (((pane_status != PANE_STATUS_OFF &&
@@ -661,7 +664,7 @@ server_client_check_mouse_in_pane(struct window_pane *wp, int px, int py,
 				return (KEYC_MOUSE_LOCATION_SCROLLBAR_DOWN);
 		} else if (window_pane_is_floating(wp) &&
 		    window_pane_get_pane_lines(wp) != PANE_LINES_NONE &&
-		    (px == wp->xoff - 1 ||
+		    (px == bdr_left ||
 		    py == wp->yoff - 1 ||
 		    py == wp->yoff + (int)wp->sy)) {
 			/* Floating pane left, bottom or top border. */
@@ -679,11 +682,20 @@ server_client_check_mouse_in_pane(struct window_pane *wp, int px, int py,
 			if (window_pane_is_floating(fwp) &&
 			    window_pane_get_pane_lines(fwp) == PANE_LINES_NONE)
 				continue;
+			if (window_pane_show_scrollbar(fwp, sb)) {
+				sb_w = fwp->scrollbar_style.width;
+				sb_pad = fwp->scrollbar_style.pad;
+			} else {
+				sb_w = 0;
+				sb_pad = 0;
+			}
 			bdr_top = fwp->yoff - 1;
 			bdr_bottom = fwp->yoff + fwp->sy;
-			if (sb_pos == PANE_SCROLLBARS_LEFT)
+			bdr_left = fwp->xoff - 1;
+			if (sb_pos == PANE_SCROLLBARS_LEFT) {
+				bdr_left -= sb_pad + sb_w;
 				bdr_right = fwp->xoff + fwp->sx;
-			else {
+			} else {
 				/* PANE_SCROLLBARS_RIGHT or none. */
 				bdr_right = fwp->xoff + fwp->sx + sb_pad + sb_w;
 			}
@@ -693,13 +705,11 @@ server_client_check_mouse_in_pane(struct window_pane *wp, int px, int py,
 					break;
 				if (window_pane_is_floating(wp)) {
 					/* Floating pane, check left border. */
-					bdr_left = fwp->xoff - 1;
 					if (px == bdr_left)
 						break;
 				}
 			}
-			if (px >= fwp->xoff - 1 &&
-			    px <= fwp->xoff + (int)fwp->sx) {
+			if (px >= bdr_left && px <= fwp->xoff + (int)fwp->sx) {
 				bdr_bottom = fwp->yoff + fwp->sy;
 				if (py == bdr_bottom)
 					break;