diff --git a/lib/ace/scrollbar.js b/lib/ace/scrollbar.js
index 55a75b33..ad6c3b1a 100644
--- a/lib/ace/scrollbar.js
+++ b/lib/ace/scrollbar.js
@@ -54,8 +54,10 @@ var ScrollBar = function(parent) {
     // in OSX lion the scrollbars appear to have no width. In this case resize
     // the to show the scrollbar but still pretend that the scrollbar has a width
     // of 0px
+    // in Firefox 6+ scrollbar is hidden if element has the same width as scrollbar
+    // make element a little bit wider to retain scrollbar when page is zoomed 
     this.width = dom.scrollbarWidth();
-    this.element.style.width = (this.width || 15) + "px";
+    this.element.style.width = (this.width || 15) + 5 + "px";
 
     event.addListener(this.element, "scroll", this.onScroll.bind(this));
 };