tmux
diff --git a/cmd-join-pane.c b/cmd-join-pane.c
@@ -300,6 +300,7 @@ cmd_join_pane_mouse_move(struct client *c, struct mouse_event *m)
 	struct window_pane	*wp;
 	struct layout_cell	*lc;
 	int			 y, ly, x, lx;
+	int			 old_xoff, old_yoff, old_sx, old_sy;
 
 	wp = cmd_mouse_pane(m, NULL, &wl);
 	if (wp == NULL) {
@@ -321,10 +322,17 @@ cmd_join_pane_mouse_move(struct client *c, struct mouse_event *m)
 		ly = m->statusat - 1;
 
 	if (x != lx || y != ly) {
+		old_xoff = wp->xoff;
+		old_yoff = wp->yoff;
+		old_sx = wp->sx;
+		old_sy = wp->sy;
+
 		lc->g.xoff += x - lx;
 		lc->g.yoff += y - ly;
 		layout_fix_panes(w, NULL);
-		server_redraw_window(w);
+
+		window_pane_redraw_floating(w, wp, old_xoff, old_yoff, old_sx,
+		    old_sy);
 		server_redraw_window_borders(w);
 	}
 }

diff --git a/cmd-resize-pane.c b/cmd-resize-pane.c
@@ -237,6 +237,7 @@ cmd_resize_pane_mouse_resize_move_floating(struct client *c,
 	int			 y, ly, x, lx, sx, sy, new_sx, new_sy;
 	int			 left, right;
 	int			 new_xoff, new_yoff, resizes = 0;
+	int			 old_xoff, old_yoff, old_sx, old_sy;
 
 	wp = cmd_mouse_pane(m, NULL, &wl);
 	if (wp == NULL) {
@@ -247,6 +248,10 @@ cmd_resize_pane_mouse_resize_move_floating(struct client *c,
 	lc = wp->layout_cell;
 	sx = wp->sx;
 	sy = wp->sy;
+	old_xoff = wp->xoff;
+	old_yoff = wp->yoff;
+	old_sx = (int)wp->sx;
+	old_sy = (int)wp->sy;
 	left = wp->xoff - 1;
 	right = wp->xoff + sx;
 	if (window_pane_scrollbar_reserve(wp) &&
@@ -346,7 +351,8 @@ cmd_resize_pane_mouse_resize_move_floating(struct client *c,
 	}
 	if (resizes != 0) {
 		layout_fix_panes(w, NULL);
-		server_redraw_window(w);
+		window_pane_redraw_floating(w, wp, old_xoff, old_yoff, old_sx,
+		    old_sy);
 		server_redraw_window_borders(w);
 	}
 }

diff --git a/cmd-split-window.c b/cmd-split-window.c
@@ -360,6 +360,7 @@ cmd_split_window_mouse_resize(struct client *c, struct mouse_event *m)
 	enum pane_lines		 lines;
 	u_int			 sx, sy;
 	int			 x, y, xoff, yoff, border;
+	int			 old_xoff, old_yoff, old_sx, old_sy;
 
 	if (c->tty.mouse_last_pane == -1)
 		return;
@@ -415,8 +416,15 @@ cmd_split_window_mouse_resize(struct client *c, struct mouse_event *m)
 	if (sy < PANE_MINIMUM)
 		sy = PANE_MINIMUM;
 
+	old_xoff = wp->xoff;
+	old_yoff = wp->yoff;
+	old_sx = wp->sx;
+	old_sy = wp->sy;
+
 	layout_set_size(lc, sx, sy, xoff, yoff);
 	layout_fix_panes(w, NULL);
-	server_redraw_window(w);
+
+	window_pane_redraw_floating(w, wp, old_xoff, old_yoff, old_sx,
+	    old_sy);
 	server_redraw_window_borders(w);
 }
diff --git a/layout.c b/layout.c
@@ -492,16 +492,18 @@ layout_fix_panes(struct window *w, struct window_pane *skip)
 					sx = PANE_MINIMUM;
 				else
 					sx = sx - sb_w - sb_pad;
-			wp->flags |= PANE_REDRAWSCROLLBAR;
 		}
 
 		window_pane_resize(wp, sx, sy);
 
 		if (wp->xoff != old_xoff ||
 		    wp->yoff != old_yoff ||
 		    wp->sx != old_sx ||
-		    wp->sy != old_sy)
+		    wp->sy != old_sy) {
 			changed = 1;
+			if (window_pane_scrollbar_reserve(wp))
+				wp->flags |= PANE_REDRAWSCROLLBAR;
+		}
 	}
 	if (changed)
 		redraw_invalidate_scene(w);

diff --git a/popup.c b/popup.c
@@ -135,7 +135,8 @@ popup_reapply_styles(struct popup_data *pd)
 }
 
 static void
-popup_redraw_cb(const struct tty_ctx *ttyctx)
+popup_redraw_cb(const struct tty_ctx *ttyctx, __unused u_int py,
+    __unused u_int ny)
 {
 	struct popup_data	*pd = ttyctx->arg;
 
@@ -320,11 +321,60 @@ popup_resize_cb(__unused struct client *c, void *data)
 	}
 }
 
+/*
+ * Report damage for a popup's rectangle, given in raw client/tty
+ * coordinates. Status-line cells are outside the window scene - they have no
+ * corresponding window content and redraw_damage_window() can't reach them -
+ * so if the popup's rectangle overlaps the status line, force it to redraw
+ * separately. The rest of the rectangle is clipped to the actual pane area
+ * (above or below the status line, whichever side it's on) before being
+ * translated into window coordinates and reported the normal way, the same
+ * way mouse coordinates are translated elsewhere (e.g. cmd-join-pane.c,
+ * cmd-split-window.c).
+ */
+static void
+popup_damage(struct client *c, u_int px, u_int py, u_int sx, u_int sy)
+{
+	struct window	*w;
+	int		 statusat;
+	u_int		 ox, oy, osx, osy, lines, top, bottom, y0, y1;
+
+	if (c->session == NULL)
+		return;
+	w = c->session->curw->window;
+
+	lines = status_line_size(c);
+	statusat = status_at_line(c);
+	if (statusat >= 0 && py < (u_int)statusat + lines &&
+	    py + sy > (u_int)statusat)
+		c->flags |= (CLIENT_REDRAWSTATUS|CLIENT_REDRAWSTATUSALWAYS);
+
+	if (statusat == 0) {
+		top = lines;
+		bottom = c->tty.sy;
+	} else if (statusat > 0) {
+		top = 0;
+		bottom = statusat;
+	} else {
+		top = 0;
+		bottom = c->tty.sy;
+	}
+	y0 = (py > top) ? py : top;
+	y1 = (py + sy < bottom) ? py + sy : bottom;
+	if (y0 >= y1)
+		return;
+
+	tty_window_offset(&c->tty, &ox, &oy, &osx, &osy);
+	redraw_damage_window(w, px + ox, y0 - top + oy, sx, y1 - y0);
+}
+
 static void
 popup_handle_drag(struct client *c, struct popup_data *pd,
     struct mouse_event *m)
 {
 	u_int	px, py;
+	u_int	old_px = pd->px, old_py = pd->py;
+	u_int	old_sx = pd->sx, old_sy = pd->sy;
 
 	if (!MOUSE_DRAG(m->b))
 		pd->dragging = OFF;
@@ -347,7 +397,9 @@ popup_handle_drag(struct client *c, struct popup_data *pd,
 		pd->dy = m->y - pd->py;
 		pd->ppx = px;
 		pd->ppy = py;
-		server_redraw_client(c);
+
+		popup_damage(c, old_px, old_py, old_sx, old_sy);
+		c->flags |= CLIENT_REDRAWOVERLAY;
 	} else if (pd->dragging == SIZE) {
 		if (pd->border_lines == BOX_LINES_NONE) {
 			if (m->x < pd->px + 1)
@@ -374,7 +426,9 @@ popup_handle_drag(struct client *c, struct popup_data *pd,
 			if (pd->job != NULL)
 				job_resize(pd->job, pd->sx - 2, pd->sy - 2);
 		}
-		server_redraw_client(c);
+
+		popup_damage(c, old_px, old_py, old_sx, old_sy);
+		c->flags |= CLIENT_REDRAWOVERLAY;
 	}
 }
 

diff --git a/regress/floating-pane-drag-ghost.sh b/regress/floating-pane-drag-ghost.sh
@@ -0,0 +1,108 @@
+#!/bin/sh
+
+# Regression test for a floating-pane drag bug: cmd_resize_pane_redraw_floating()
+# (cmd-resize-pane.c) reported damage for just a dragged floating pane's
+# content rectangle, not the one-cell border frame drawn around it (see the
+# "floating" case in screen-redraw.c, which draws that frame at
+# xoff-1/yoff-1 through xoff+sx/yoff+sy - one cell outside the pane's own
+# content area). Damage scoped to only the content area left the frame's
+# previous position undrawn as the pane moved, so dragging it left a trail
+# of un-erased border frames behind - visible as several "corners" stacked
+# up rather than just the pane's current one.
+#
+# This bug has nothing to do with images - it reproduces with a plain
+# floating pane and no image support required.
+
+PATH=/bin:/usr/bin
+TERM=screen
+LC_ALL=C.UTF-8
+export TERM LC_ALL
+
+[ -z "$TEST_TMUX" ] && TEST_TMUX=$(readlink -f ../tmux)
+TMUX="$TEST_TMUX -LtestA$$ -f/dev/null"
+TMUX2="$TEST_TMUX -LtestB$$ -f/dev/null"
+
+cleanup()
+{
+	$TMUX kill-server >/dev/null 2>&1
+	$TMUX2 kill-server >/dev/null 2>&1
+}
+fail()
+{
+	echo "$*" >&2
+	cleanup
+	exit 1
+}
+
+# drag STARTCOL STARTROW ENDCOL ENDROW
+#
+# Write a plain (unmodified) SGR button-1 press, drag update and release at
+# 1-based positions to the outer pane holding the inner client - this
+# matches the default MouseDown1Border/MouseDrag1Border bindings used to
+# move or resize a floating pane by its border.
+drag()
+{
+	scol="$1"
+	srow="$2"
+	ecol="$3"
+	erow="$4"
+
+	seq=$(printf '\033[<0;%s;%sM' "$scol" "$srow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 0.2
+	seq=$(printf '\033[<32;%s;%sM' "$ecol" "$erow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 0.2
+	seq=$(printf '\033[<0;%s;%sm' "$ecol" "$erow")
+	$TMUX2 send-keys -t "$OUTER" -l "$seq" 2>/dev/null
+	sleep 1
+}
+
+cleanup
+
+TMP=$(mktemp)
+trap "cleanup; rm -f $TMP" 0 1 15
+
+$TMUX new-session -d -s inner -x 60 -y 20 'sh -c "sleep 100"' || exit 1
+$TMUX set -g mouse on
+$TMUX set -g default-command 'sh -c "sleep 100"'
+
+FLOAT=$($TMUX new-pane -d -PF '#{pane_id}' -x 16 -y 5 -X 5 -Y 5) ||
+	fail "new-pane -X -Y failed"
+FTOP=$($TMUX display-message -p -t "$FLOAT" '#{pane_top}')
+FLEFT=$($TMUX display-message -p -t "$FLOAT" '#{pane_left}')
+FWIDTH=$($TMUX display-message -p -t "$FLOAT" '#{pane_width}')
+
+$TMUX2 new-session -d -x 60 -y 20 "$TMUX attach -t inner" || exit 1
+sleep 1
+OUTER=$($TMUX2 list-panes -F '#{pane_id}' | head -1)
+[ -n "$OUTER" ] || fail "No outer pane."
+
+# Sanity check: exactly one floating pane, so exactly one top-left corner,
+# before dragging anything.
+$TMUX2 capturep -p -t "$OUTER" >$TMP || fail "capture failed"
+n=$(grep -o '┌' $TMP | wc -l)
+[ "$n" -eq 1 ] || fail "sanity: expected 1 corner before drag, found $n"
+
+# Drag the floating pane by its top border (row FTOP-1, some column within
+# its width) down several rows in a few separate steps, then release. A
+# single drag() call already does press/motion/release, so call it several
+# times in a row to simulate a multi-step real drag.
+GRABCOL=$((FLEFT + FWIDTH / 2))
+STARTROW=$FTOP
+i=0
+while [ $i -lt 6 ]; do
+	newrow=$((STARTROW + i + 1))
+	drag $((GRABCOL + 1)) $((STARTROW + i)) $((GRABCOL + 1)) $newrow
+	i=$((i + 1))
+done
+
+$TMUX2 capturep -p -t "$OUTER" >$TMP || fail "capture failed"
+
+# Exactly one top-left corner should remain - the pane's current position.
+# This is expected to fail before the fix: multiple corners (a trail of
+# un-erased frames) would remain from the intermediate drag positions.
+n=$(grep -o '┌' $TMP | wc -l)
+[ "$n" -eq 1 ] || fail "expected exactly 1 corner after drag, found $n (ghost frames left behind)"
+
+exit 0