diff --git a/src/xdisp.c b/src/xdisp.c
index 9247d5bc3e1..9a82953952f 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -16897,6 +16897,7 @@ redisplay_window (Lisp_Object window, bool just_this_one_p)
       /* We used to issue a CHECK_MARGINS argument to try_window here,
 	 but this causes scrolling to fail when point begins inside
 	 the scroll margin (bug#148) -- cyd  */
+      clear_glyph_matrix (w->desired_matrix);
       if (!try_window (window, startp, 0))
 	{
 	  w->force_start = true;