diff --git a/lib/ace/virtual_renderer.js b/lib/ace/virtual_renderer.js
index 477b5ca9..37acb23e 100644
--- a/lib/ace/virtual_renderer.js
+++ b/lib/ace/virtual_renderer.js
@@ -962,6 +962,8 @@ var VirtualRenderer = function(container, theme) {
         offset = this.scrollTop - firstRowScreen * lineHeight;
 
         var changes = 0;
+        if (this.layerConfig.width != longestLine) 
+            changes = this.CHANGE_H_SCROLL;
         // Horizontal scrollbar visibility may have changed, which changes
         // the client height of the scroller
         if (hScrollChanged || vScrollChanged) {