The Tor Browser / file revision

 /* This Source Code Form is subject to the terms of the Mozilla Public

  * License, v. 2.0. If a copy of the MPL was not distributed with this file,

  * You can obtain one at http://mozilla.org/MPL/2.0/. */

 "use strict";

 var Feedback = {

   observe: function(aMessage, aTopic, aData) {

     if (aTopic !== "Feedback:Show")

       return;

     // Only prompt for feedback if this isn't a distribution build.

     try {

       Services.prefs.getCharPref("distribution.id");

     } catch (e) {

       BrowserApp.addTab("about:feedback", { selected: true, parentId: BrowserApp.selectedTab.id });

     }

   }

 };