--- a/mobile/chrome/content/bindings/browser.xml
+++ b/mobile/chrome/content/bindings/browser.xml
@@ -183,19 +183,20 @@
             });
 
             this._browser.messageManager.sendAsyncMessage("WebProgress:AddProgressListener", {
               notifyFlags: aNotifyFlags,
             });
           },
 
           removeProgressListener: function(aListener) {
+            let self = this;
             function hasFilter(item) {
               if (item.listener == aListener)
-                this._browser.messageManager.sendAsyncMessage("WebProgress:RemoveProgressListener", {
+                self._browser.messageManager.sendAsyncMessage("WebProgress:RemoveProgressListener", {
                   notifyFlags: item.flags,
                 });
               return item.listener != aListener;
             }
 
             this._listeners = this._listeners.filter(hasFilter);
           },
           get DOMWindow() { throw "DOMWindow: Not Remoteable" },