1 files changed, 4 insertions, 0 deletions

diff --git a/src/buffer.c b/src/buffer.c
index 9388025808c..c817ebc167e 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -3649,6 +3649,10 @@ modify_overlay (buf, start, end)
   /* If multiple windows show this buffer, we must do other windows.  */
   else if (buffer_shared > 1)
     windows_or_buffers_changed = 1;
+  /* If we modify an overlay at the end of the buffer, we cannot
+     be sure that window end is still valid.  */
+  else if (end >= ZV && start <= ZV)
+    windows_or_buffers_changed = 1;
 
   ++BUF_OVERLAY_MODIFF (buf);
 }