diff -r 000000000000 -r 6474c204b198 browser/base/content/test/general/browser_bug735471.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/base/content/test/general/browser_bug735471.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,55 @@
+/*
+ * 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/.
+ */
+
+
+function test() {
+  waitForExplicitFinish();
+  registerCleanupFunction(function() {
+    // Reset pref to its default
+    Services.prefs.clearUserPref("browser.preferences.inContent");
+  });
+  
+  // Verify that about:preferences tab is displayed when
+  // browser.preferences.inContent is set to true
+  Services.prefs.setBoolPref("browser.preferences.inContent", true);
+
+  // Open a new tab.
+  whenNewTabLoaded(window, testPreferences);
+}
+
+function testPreferences() {
+  whenTabLoaded(gBrowser.selectedTab, function () {
+    is(Services.prefs.getBoolPref("browser.preferences.inContent"), true, "In-content prefs are enabled");
+    is(content.location.href, "about:preferences", "Checking if the preferences tab was opened");
+
+    gBrowser.removeCurrentTab();
+    Services.prefs.setBoolPref("browser.preferences.inContent", false);
+    openPreferences();
+  });
+  
+  let observer = {
+    observe: function(aSubject, aTopic, aData) {
+      if (aTopic == "domwindowopened") {
+        windowWatcher.unregisterNotification(observer);
+        
+        let win = aSubject.QueryInterface(Components.interfaces.nsIDOMWindow);
+        win.addEventListener("load", function() {
+          win.removeEventListener("load", arguments.callee, false);
+          is(Services.prefs.getBoolPref("browser.preferences.inContent"), false, "In-content prefs are disabled");
+          is(win.location.href, "chrome://browser/content/preferences/preferences.xul", "Checking if the preferences window was opened");
+          win.close();
+          finish();
+        }, false);
+      }
+    }
+  }
+  
+  var windowWatcher = Components.classes["@mozilla.org/embedcomp/window-watcher;1"]
+                        .getService(Components.interfaces.nsIWindowWatcher);
+  windowWatcher.registerNotification(observer);
+  
+  openPreferences();
+}