The Tor Browser / file revision

 /* Any copyright is dedicated to the Public Domain.

    http://creativecommons.org/publicdomain/zero/1.0/ */

 /**

  * These tests ensure that capturing a sites's thumbnail, saving it and

  * retrieving it from the cache works.

  */

 function runTests() {

   // Create a tab that shows an error page.

   let tab = gBrowser.addTab("http://127.0.0.1:1/");

   let browser = tab.linkedBrowser;

   yield browser.addEventListener("DOMContentLoaded", function onLoad() {

     browser.removeEventListener("DOMContentLoaded", onLoad, false);

     executeSoon(next);

   }, false);

   ok(!gBrowserThumbnails._shouldCapture(browser), "we're not going to capture an error page");

 }