diff --git a/cmd-copy-mode.c b/cmd-copy-mode.c
index eae7698fd..fce6d3fbd 100644
--- a/cmd-copy-mode.c
+++ b/cmd-copy-mode.c
@@ -63,6 +63,7 @@ cmd_copy_mode_exec(struct cmd *self, struct cmdq_item *item)
 	struct client		*c = cmdq_get_client(item);
 	struct session		*s;
 	struct window_pane	*wp = target->wp, *swp;
+	u_int			 tty_ox, tty_oy, tty_sx, tty_sy;
 	int			 line_numbers;
 
 	if (args_has(args, 'q')) {
@@ -100,8 +101,9 @@ cmd_copy_mode_exec(struct cmd *self, struct cmdq_item *item)
 	if (args_has(args, 'd'))
 		window_copy_pagedown(wp, 0, args_has(args, 'e'));
 	if (args_has(args, 'S')) {
+		tty_window_offset(&c->tty, &tty_ox, &tty_oy, &tty_sx, &tty_sy);
 		window_copy_scroll(wp, c->tty.mouse_slider_mpos, event->m.y,
-		    args_has(args, 'e'));
+		    tty_oy, args_has(args, 'e'));
 		return (CMD_RETURN_NORMAL);
 	}
 
diff --git a/cmd-join-pane.c b/cmd-join-pane.c
index 8444a2304..c1e879b67 100644
--- a/cmd-join-pane.c
+++ b/cmd-join-pane.c
@@ -71,11 +71,8 @@ cmd_join_pane_exec(struct cmd *self, struct cmdq_item *item)
 	struct window		*src_w, *dst_w;
 	struct window_pane	*src_wp, *dst_wp;
 	char			*cause = NULL;
-	int			 size, dst_idx;
-	int			 flags;
-	enum layout_type	 type;
+	int			 flags = 0, dst_idx;
 	struct layout_cell	*lc;
-	u_int			 curval = 0;
 
 	dst_s = target->s;
 	dst_wl = target->wl;
@@ -94,53 +91,13 @@ cmd_join_pane_exec(struct cmd *self, struct cmdq_item *item)
 		return (CMD_RETURN_ERROR);
 	}
 
-	type = LAYOUT_TOPBOTTOM;
-	if (args_has(args, 'h'))
-		type = LAYOUT_LEFTRIGHT;
-
-	/* If the 'p' flag is dropped then this bit can be moved into 'l'. */
-	if (args_has(args, 'l') || args_has(args, 'p')) {
-		if (args_has(args, 'f')) {
-			if (type == LAYOUT_TOPBOTTOM)
-				curval = dst_w->sy;
-			else
-				curval = dst_w->sx;
-		} else {
-			if (type == LAYOUT_TOPBOTTOM)
-				curval = dst_wp->sy;
-			else
-				curval = dst_wp->sx;
-		}
-	}
-
-	size = -1;
-	if (args_has(args, 'l')) {
-		size = args_percentage_and_expand(args, 'l', 0, INT_MAX, curval,
-			   item, &cause);
-	} else if (args_has(args, 'p')) {
-		size = args_strtonum_and_expand(args, 'p', 0, 100, item,
-			   &cause);
-		if (cause == NULL)
-			size = curval * size / 100;
-	}
+	lc = layout_get_tiled_cell(item, args, dst_w, dst_wp, flags, &cause);
 	if (cause != NULL) {
-		cmdq_error(item, "size %s", cause);
+		cmdq_error(item, "%s", cause);
 		free(cause);
 		return (CMD_RETURN_ERROR);
 	}
 
-	flags = 0;
-	if (args_has(args, 'b'))
-		flags |= SPAWN_BEFORE;
-	if (args_has(args, 'f'))
-		flags |= SPAWN_FULLSIZE;
-
-	lc = layout_split_pane(dst_wp, type, size, flags);
-	if (lc == NULL) {
-		cmdq_error(item, "create pane failed: pane too small");
-		return (CMD_RETURN_ERROR);
-	}
-
 	layout_close_pane(src_wp);
 
 	server_client_remove_pane(src_wp);
diff --git a/cmd-split-window.c b/cmd-split-window.c
index b138b9b97..2f0c9a460 100644
--- a/cmd-split-window.c
+++ b/cmd-split-window.c
@@ -108,7 +108,8 @@ cmd_split_window_exec(struct cmd *self, struct cmdq_item *item)
 	else
 		lc = layout_get_tiled_cell(item, args, w, wp, flags, &cause);
 	if (cause != NULL) {
-		cmdq_error(item, "could not create cell: %s", cause);
+		cmdq_error(item, "%s", cause);
+		free(cause);
 		return (CMD_RETURN_ERROR);
 	}
 
diff --git a/format.c b/format.c
index b87b5f21d..d94c724d9 100644
--- a/format.c
+++ b/format.c
@@ -5616,7 +5616,7 @@ format_expand1(struct format_expand_state *es, const char *fmt)
 	const char		*ptr, *s, *style_end = NULL;
 	size_t			 off, len, n, outlen;
 	int			 ch, brackets;
-	char			 expanded[8192], number[2] = { 0 };
+	char			 expanded[8192];
 
 	if (fmt == NULL || *fmt == '\0' || !format_check_time(es))
 		return (xstrdup(""));
@@ -5746,13 +5746,6 @@ format_expand1(struct format_expand_state *es, const char *fmt)
 			continue;
 		default:
 			s = NULL;
-			if (ch >= '1' && ch <= '9') {
-				number[0] = ch;
-				if (format_replace(es, number, 1, &buf, &len,
-				    &off) != 0)
-					break;
-				continue;
-			}
 			if (fmt > style_end) { /* skip inside #[] */
 				if (ch >= 'A' && ch <= 'Z')
 					s = format_upper[ch - 'A'];
diff --git a/tmux.1 b/tmux.1
index 11bf5a612..4e0534f92 100644
--- a/tmux.1
+++ b/tmux.1
@@ -7872,9 +7872,6 @@ section.
 If
 .Ar argument
 values are given, they are available as
-.Ql #1 ,
-.Ql #2
-or
 .Ql #{1} ,
 .Ql #{2}
 and so on.
diff --git a/tmux.h b/tmux.h
index 125e0207b..c76df0e32 100644
--- a/tmux.h
+++ b/tmux.h
@@ -3619,7 +3619,7 @@ void printflike(3, 4) window_copy_add(struct window_pane *, int, const char *,
 		     ...);
 void printflike(3, 0) window_copy_vadd(struct window_pane *, int, const char *,
 		     va_list);
-void		 window_copy_scroll(struct window_pane *, int, u_int, int);
+void		 window_copy_scroll(struct window_pane *, int, u_int, u_int, int);
 void		 window_copy_pageup(struct window_pane *, int);
 void		 window_copy_pagedown(struct window_pane *, int, int);
 void		 window_copy_start_drag(struct client *, struct mouse_event *);
diff --git a/tty.c b/tty.c
index c63767137..f201ba1d1 100644
--- a/tty.c
+++ b/tty.c
@@ -1004,7 +1004,7 @@ tty_window_offset1(struct tty *tty, u_int *ox, u_int *oy, u_int *sx, u_int *sy)
 		else if (cy > w->sy - *sy)
 			*oy = w->sy - *sy;
 		else
-			*oy = cy - *sy / 2;
+			*oy = cy - *sy + 1;
 	}
 
 	c->pan_window = NULL;
diff --git a/window-copy.c b/window-copy.c
index a02c99c1b..39ae18816 100644
--- a/window-copy.c
+++ b/window-copy.c
@@ -42,7 +42,7 @@ static void	window_copy_formats(struct window_mode_entry *,
 		    struct format_tree *);
 static struct screen *window_copy_get_screen(struct window_mode_entry *);
 static void	window_copy_scroll1(struct window_mode_entry *,
-		    struct window_pane *wp, int, u_int, int);
+		    struct window_pane *, int, u_int, u_int, int);
 static void	window_copy_pageup1(struct window_mode_entry *, int);
 static int	window_copy_pagedown1(struct window_mode_entry *, int, int);
 static void	window_copy_next_paragraph(struct window_mode_entry *);
@@ -629,19 +629,19 @@ window_copy_vadd(struct window_pane *wp, int parse, const char *fmt, va_list ap)
 
 void
 window_copy_scroll(struct window_pane *wp, int sl_mpos, u_int my,
-    int scroll_exit)
+    u_int tty_oy, int scroll_exit)
 {
 	struct window_mode_entry	*wme = TAILQ_FIRST(&wp->modes);
 
 	if (wme != NULL) {
 		window_set_active_pane(wp->window, wp, 0);
-		window_copy_scroll1(wme, wp, sl_mpos, my, scroll_exit);
+		window_copy_scroll1(wme, wp, sl_mpos, my, tty_oy, scroll_exit);
 	}
 }
 
 static void
 window_copy_scroll1(struct window_mode_entry *wme, struct window_pane *wp,
-    int sl_mpos, u_int my, int scroll_exit)
+    int sl_mpos, u_int my, u_int tty_oy, int scroll_exit)
 {
 	struct window_copy_mode_data	*data = wme->data;
 	u_int				 ox, oy, px, py, n, offset, size;
@@ -649,21 +649,29 @@ window_copy_scroll1(struct window_mode_entry *wme, struct window_pane *wp,
 	u_int				 slider_height = wp->sb_slider_h;
 	u_int				 sb_height = wp->sy, sb_top = wp->yoff;
 	u_int				 sy = screen_size_y(data->backing);
+	u_int				 my_w;
 	int				 new_slider_y, delta;
 
 	/*
 	 * sl_mpos is where in the slider the user is dragging, mouse is
 	 * dragging this y point relative to top of slider.
+	 *
+	 * my is a raw tty y coordinate; sb_top (= wp->yoff) is a window
+	 * coordinate. Convert my to window coordinates by adding tty_oy (the
+	 * window pan offset). sl_mpos already has the status lines adjustment
+	 * baked in (see server_client_check_mouse), so no further status lines
+	 * correction is needed here.
 	 */
-	if (my <= sb_top + sl_mpos) {
+	my_w = my + tty_oy;
+	if (my_w <= sb_top + (u_int)sl_mpos) {
 		/* Slider banged into top. */
 		new_slider_y = sb_top - wp->yoff;
-	} else if (my - sl_mpos > sb_top + sb_height - slider_height) {
+	} else if (my_w - sl_mpos > sb_top + sb_height - slider_height) {
 		/* Slider banged into bottom. */
 		new_slider_y = sb_top - wp->yoff + (sb_height - slider_height);
 	} else {
 		/* Slider is somewhere in the middle. */
-		new_slider_y = my - wp->yoff - sl_mpos;
+		new_slider_y = my_w - wp->yoff - sl_mpos;
 	}
 
 	if (TAILQ_FIRST(&wp->modes) == NULL ||
@@ -1548,8 +1556,11 @@ window_copy_cmd_scroll_to_mouse(struct window_copy_cmd_state *cs)
 	struct client			*c = cs->c;
 	struct mouse_event		*m = cs->m;
 	int				 scroll_exit = args_has(cs->wargs, 'e');
+	u_int				 tty_ox, tty_oy, tty_sx, tty_sy;
 
-	window_copy_scroll(wp, c->tty.mouse_slider_mpos, m->y, scroll_exit);
+	tty_window_offset(&c->tty, &tty_ox, &tty_oy, &tty_sx, &tty_sy);
+	window_copy_scroll(wp, c->tty.mouse_slider_mpos, m->y, tty_oy,
+	    scroll_exit);
 	return (WINDOW_COPY_CMD_NOTHING);
 }
 
@@ -4981,7 +4992,7 @@ window_copy_write_lines(struct window_mode_entry *wme,
 	u_int	yy;
 
 	for (yy = py; yy < py + ny; yy++)
-		window_copy_write_line(wme, ctx, py);
+		window_copy_write_line(wme, ctx, yy);
 }
 
 static void