diff --git a/js/ui/messageTray.js b/js/ui/messageTray.js
index 8c7dbf818..5c57c9c2e 100644
--- a/js/ui/messageTray.js
+++ b/js/ui/messageTray.js
@@ -2011,9 +2011,15 @@ MessageTray.prototype = {
         this._notification.expand(!autoExpanding);
     },
 
-   _onNotificationExpanded: function() {
+    _onNotificationExpanded: function() {
         let expandedY = this.actor.height - this._notificationBin.height;
-        if (this._notificationBin.y != expandedY)
+
+        // Don't animate the notification to its new position if it has shrunk:
+        // there will be a very visible "gap" that breaks the illusion.
+
+        if (this._notificationBin.y < expandedY)
+            this._notificationBin.y = expandedY;
+        else if (this._notification.y != expandedY)
             this._tween(this._notificationBin, '_notificationState', State.SHOWN,
                         { y: expandedY,
                           time: ANIMATION_TIME,