diff --git a/lib/ace/VirtualRenderer.js b/lib/ace/VirtualRenderer.js
index d7324e17..67bb1482 100644
--- a/lib/ace/VirtualRenderer.js
+++ b/lib/ace/VirtualRenderer.js
@@ -408,10 +408,7 @@ var VirtualRenderer = function(container, theme) {
     this.$updateLines = function() {
         var firstRow = this.$changedLines.firstRow;
         var lastRow = this.$changedLines.lastRow;
-        this.$changedLines = {
-            firstRow: 0,
-            lastRow: Infinity
-        };
+        this.$changedLines = null;
 
         var layerConfig = this.layerConfig;