diff --git a/lib/ace/virtual_renderer.js b/lib/ace/virtual_renderer.js
index 0ef71f36..dbe54ea6 100644
--- a/lib/ace/virtual_renderer.js
+++ b/lib/ace/virtual_renderer.js
@@ -720,7 +720,8 @@ var VirtualRenderer = function(container, theme) {
             changes & this.CHANGE_SIZE ||
             changes & this.CHANGE_TEXT ||
             changes & this.CHANGE_LINES ||
-            changes & this.CHANGE_SCROLL
+            changes & this.CHANGE_SCROLL ||
+            changes & this.CHANGE_H_SCROLL
         )
             this.$computeLayerConfig();
 
@@ -1262,7 +1263,9 @@ var VirtualRenderer = function(container, theme) {
         if (deltaY > 0 && this.session.getScrollTop() + this.$size.scrollerHeight
             - this.layerConfig.maxHeight < -1 + this.scrollMargin.bottom)
            return true;
-        // todo: handle horizontal scrolling
+        // todo: better handle horizontal scrolling
+        if (deltaX)
+           return true;
     };
 
     this.pixelToScreenCoordinates = function(x, y) {