diff -r 000000000000 -r 6474c204b198 addon-sdk/source/lib/sdk/windows.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/addon-sdk/source/lib/sdk/windows.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,36 @@
+/* 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';
+
+module.metadata = {
+  'stability': 'stable',
+  'engines': {
+    'Firefox': '*',
+    'Fennec': '*'
+  }
+};
+
+const { isBrowser } = require('./window/utils');
+const { modelFor } = require('./model/core');
+const { viewFor } = require('./view/core');
+
+
+if (require('./system/xul-app').is('Fennec')) {
+  module.exports = require('./windows/fennec');
+}
+else {
+  module.exports = require('./windows/firefox');
+}
+
+
+const browsers = module.exports.browserWindows;
+
+//
+modelFor.when(isBrowser, view => {
+  for (let model of browsers) {
+    if (viewFor(model) === view)
+      return model;
+  }
+  return null;
+});