--- a/toolkit/content/browser-content.js
+++ b/toolkit/content/browser-content.js
@@ -134,16 +134,22 @@ var ClickEventHandler = {
 
   startScroll(event) {
 
     this.findNearestScrollableElement(event.originalTarget);
 
     if (!this._scrollable)
       return;
 
+    // In some configurations like Print Preview, content.performance
+    // (which we use below) is null. Autoscrolling is broken in Print
+    // Preview anyways (see bug 1393494), so just don't start it at all.
+    if (!content.performance)
+      return;
+
     let domUtils = content.QueryInterface(Ci.nsIInterfaceRequestor)
                           .getInterface(Ci.nsIDOMWindowUtils);
     let scrollable = this._scrollable;
     if (scrollable instanceof Ci.nsIDOMWindow) {
       // getViewId() needs an element to operate on.
       scrollable = scrollable.document.documentElement;
     }
     this._scrollId = null;