diff --git a/addon-sdk/source/doc/dev-guide-source/tutorials/getting-started-with-cfx.md b/addon-sdk/source/doc/dev-guide-source/tutorials/getting-started-with-cfx.md
index cb56d3b53c3..749b180a52f 100644
--- a/addon-sdk/source/doc/dev-guide-source/tutorials/getting-started-with-cfx.md
+++ b/addon-sdk/source/doc/dev-guide-source/tutorials/getting-started-with-cfx.md
@@ -96,7 +96,7 @@ package.json modified: please re-run 'cfx run'
 alt="Mozilla icon widget" />
 
 Run `cfx run` again, and it will run an instance of Firefox. In the
-bottom-right corner of the browser you'll see an icon with the Firefox
+bottom-right corner of the browser you'll see an icon with the Mozilla
 logo. Click the icon, and a new tab will open with
 [http://www.mozilla.org/](http://www.mozilla.org/) loaded into it.
 
diff --git a/addon-sdk/source/doc/module-source/sdk/window/utils.md b/addon-sdk/source/doc/module-source/sdk/window/utils.md
index 22135da28b5..e8e1f394330 100644
--- a/addon-sdk/source/doc/module-source/sdk/window/utils.md
+++ b/addon-sdk/source/doc/module-source/sdk/window/utils.md
@@ -89,7 +89,7 @@ to support private browsing, refer to the
       var utils = require('sdk/window/utils');
       var browserWindow = utils.getMostRecentBrowserWindow();
       var window = browserWindow.content; // `window` object for the current webpage
-      utils.getToplevelWindw(window) == browserWindow // => true
+      utils.getToplevelWindow(window) == browserWindow // => true
 
   @param window {nsIDOMWindow}
   @returns {nsIDOMWindow}
diff --git a/addon-sdk/source/doc/static-files/media/screenshots/widget-jquery.png b/addon-sdk/source/doc/static-files/media/screenshots/widget-jquery.png
index 4b0ad66bb7b..ce1cbdcb677 100644
Binary files a/addon-sdk/source/doc/static-files/media/screenshots/widget-jquery.png and b/addon-sdk/source/doc/static-files/media/screenshots/widget-jquery.png differ
diff --git a/addon-sdk/source/doc/static-files/media/screenshots/widget-mozilla.png b/addon-sdk/source/doc/static-files/media/screenshots/widget-mozilla.png
index 29a26a304a7..ed0555b6463 100644
Binary files a/addon-sdk/source/doc/static-files/media/screenshots/widget-mozilla.png and b/addon-sdk/source/doc/static-files/media/screenshots/widget-mozilla.png differ
diff --git a/addon-sdk/source/lib/sdk/content/content-worker.js b/addon-sdk/source/lib/sdk/content/content-worker.js
index 6c7d8fb69bb..eba9491339a 100644
--- a/addon-sdk/source/lib/sdk/content/content-worker.js
+++ b/addon-sdk/source/lib/sdk/content/content-worker.js
@@ -137,6 +137,14 @@ const ContentWorker = Object.freeze({
         registerMethod = chromeSetInterval;
       else
         throw new Error("Unknown timer kind: " + timer.kind);
+
+      if (typeof timer.fun == 'string') {
+        let code = timer.fun;
+        timer.fun = () => chromeAPI.sandbox.evaluate(exports, code);
+      } else if (typeof timer.fun != 'function') {
+        throw new Error('Unsupported callback type' + typeof timer.fun);
+      }
+
       let id = registerMethod(onFire, timer.delay);
       function onFire() {
         try {
@@ -145,12 +153,47 @@ const ContentWorker = Object.freeze({
           timer.fun.apply(null, timer.args);
         } catch(e) {
           console.exception(e);
+          let wrapper = {
+            instanceOfError: instanceOf(e, Error),
+            value: e,
+          };
+          if (wrapper.instanceOfError) {
+            wrapper.value = {
+              message: e.message,
+              fileName: e.fileName,
+              lineNumber: e.lineNumber,
+              stack: e.stack,
+              name: e.name, 
+            };
+          }
+          pipe.emit('error', wrapper);
         }
       }
       _timers[id] = timer;
       return id;
     }
 
+    // copied from sdk/lang/type.js since modules are not available here
+    function instanceOf(value, Type) {
+      var isConstructorNameSame;
+      var isConstructorSourceSame;
+
+      // If `instanceof` returned `true` we know result right away.
+      var isInstanceOf = value instanceof Type;
+
+      // If `instanceof` returned `false` we do ducktype check since `Type` may be
+      // from a different sandbox. If a constructor of the `value` or a constructor
+      // of the value's prototype has same name and source we assume that it's an
+      // instance of the Type.
+      if (!isInstanceOf && value) {
+        isConstructorNameSame = value.constructor.name === Type.name;
+        isConstructorSourceSame = String(value.constructor) == String(Type);
+        isInstanceOf = (isConstructorNameSame && isConstructorSourceSame) ||
+                        instanceOf(Object.getPrototypeOf(value), Type);
+      }
+      return isInstanceOf;
+    }
+
     function unregisterTimer(id) {
       if (!(id in _timers))
         return;
diff --git a/addon-sdk/source/lib/sdk/content/loader.js b/addon-sdk/source/lib/sdk/content/loader.js
index 8d4b04be4b4..77e4a697e37 100644
--- a/addon-sdk/source/lib/sdk/content/loader.js
+++ b/addon-sdk/source/lib/sdk/content/loader.js
@@ -13,6 +13,7 @@ const { validateOptions } = require('../deprecated/api-utils');
 const { isValidURI, URL } = require('../url');
 const file = require('../io/file');
 const { contract } = require('../util/contract');
+const { isString, instanceOf } = require('../lang/type');
 
 const LOCAL_URI_SCHEMES = ['resource', 'data'];
 
@@ -32,7 +33,7 @@ const valid = {
     msg: 'The `contentURL` option must be a valid URL.'
   },
   contentScriptFile: {
-    is: ['undefined', 'null', 'string', 'array'],
+    is: ['undefined', 'null', 'string', 'array', 'object'],
     map: ensureNull,
     ok: function(value) {
       if (value === null)
@@ -40,8 +41,13 @@ const valid = {
 
       value = [].concat(value);
 
-      // Make sure every item is a local file URL.
+      // Make sure every item is a string or an
+      // URL instance, and also a local file URL.
       return value.every(function (item) {
+
+        if (!isString(item) && !(item instanceof URL)) 
+          return false;
+
         try {
           return ~LOCAL_URI_SCHEMES.indexOf(URL(item).scheme);
         }
diff --git a/addon-sdk/source/lib/sdk/content/symbiont.js b/addon-sdk/source/lib/sdk/content/symbiont.js
index ec0eae0ebce..3fc408cdb92 100644
--- a/addon-sdk/source/lib/sdk/content/symbiont.js
+++ b/addon-sdk/source/lib/sdk/content/symbiont.js
@@ -108,6 +108,27 @@ const Symbiont = Worker.resolve({
     
     this._frame = frame;
 
+    if (getDocShell(frame)) {
+      this._reallyInitFrame(frame);
+    }
+    else {
+      if (this._waitForFrame) {
+        observers.remove('content-document-global-created', this._waitForFrame);
+      }
+      this._waitForFrame = this.__waitForFrame.bind(this, frame);
+      observers.add('content-document-global-created', this._waitForFrame);
+    }
+  },
+
+  __waitForFrame: function _waitForFrame(frame, win, topic) {
+    if (frame.contentWindow == win) {
+      observers.remove('content-document-global-created', this._waitForFrame);
+      delete this._waitForFrame;
+      this._reallyInitFrame(frame);
+    }
+  },
+
+  _reallyInitFrame: function _reallyInitFrame(frame) {
     getDocShell(frame).allowJavascript = this.allow.script;
     frame.setAttribute("src", this._contentURL);
 
@@ -179,6 +200,11 @@ const Symbiont = Worker.resolve({
    * This listener is registered in `Symbiont._initFrame`.
    */
   _unregisterListener: function _unregisterListener() {
+    if (this._waitForFrame) {
+      observers.remove('content-document-global-created', this._waitForFrame);
+      delete this._waitForFrame;
+    }
+
     if (!this._loadListener)
       return;
     if (this._loadEvent == "start") {
diff --git a/addon-sdk/source/lib/sdk/content/worker.js b/addon-sdk/source/lib/sdk/content/worker.js
index cd37ea913aa..3efcf90d213 100644
--- a/addon-sdk/source/lib/sdk/content/worker.js
+++ b/addon-sdk/source/lib/sdk/content/worker.js
@@ -202,8 +202,15 @@ const WorkerSandbox = EventEmitter.compose({
           clearInterval: 'r'
         }
       },
+      sandbox: {
+        evaluate: evaluate,
+        __exposedProps__: {
+          evaluate: 'r',
+        }
+      },
       __exposedProps__: {
-        timers: 'r'
+        timers: 'r',
+        sandbox: 'r',
       }
     };
     let onEvent = this._onContentEvent.bind(this);
@@ -233,6 +240,19 @@ const WorkerSandbox = EventEmitter.compose({
         self._addonWorker._onContentScriptEvent.apply(self._addonWorker, arguments);
     });
 
+    // unwrap, recreate and propagate async Errors thrown from content-script
+    this.on("error", function onError({instanceOfError, value}) {
+      if (self._addonWorker) {
+        let error = value;
+        if (instanceOfError) {
+          error = new Error(value.message, value.fileName, value.lineNumber);
+          error.stack = value.stack;
+          error.name = value.name;
+        }
+        self._addonWorker._emit('error', error);
+      }
+    });
+
     // Inject `addon` global into target document if document is trusted,
     // `addon` in document is equivalent to `self` in content script.
     if (worker._injectInDocument) {
diff --git a/addon-sdk/source/lib/sdk/event/core.js b/addon-sdk/source/lib/sdk/event/core.js
index 76ead4142ba..b45428d7bbc 100644
--- a/addon-sdk/source/lib/sdk/event/core.js
+++ b/addon-sdk/source/lib/sdk/event/core.js
@@ -36,7 +36,7 @@ const observers = function observers(target, type) {
  *    The listener function that processes the event.
  */
 function on(target, type, listener) {
-   if (typeof(listener) !== 'function')
+  if (typeof(listener) !== 'function')
     throw new Error(BAD_LISTENER);
 
   let listeners = observers(target, type);
@@ -56,9 +56,9 @@ exports.on = on;
  *    The listener function that processes the event.
  */
 function once(target, type, listener) {
-  on(target, type, function observer() {
+  on(target, type, function observer(...args) {
     off(target, type, observer);
-    listener.apply(target, arguments);
+    listener.apply(target, args);
   });
 }
 exports.once = once;
@@ -74,40 +74,24 @@ exports.once = once;
  *    Event target object.
  * @param {String} type
  *    The type of event.
- * @params {Object|Number|String|Boolean} message
- *    First argument that will be passed to listeners.
- * @params {Object|Number|String|Boolean} ...
- *    More arguments that will be passed to listeners.
+ * @params {Object|Number|String|Boolean} args
+ *    Arguments that will be passed to listeners.
  */
-function emit(target, type, message /*, ...*/) {
-  for each (let item in emit.lazy.apply(emit.lazy, arguments)) {
-    // We just iterate, iterator take care of emitting events.
-  }
-}
-
-/**
- * This is very experimental feature that you should not use unless absolutely
- * need it. Also it may be removed at any point without any further notice.
- *
- * Creates lazy iterator of return values of listeners. You can think of it
- * as lazy array of return values of listeners for the `emit` with the given
- * arguments.
- */
-emit.lazy = function lazy(target, type, message /*, ...*/) {
-  let args = Array.slice(arguments, 2);
+function emit (target, type, ...args) {
   let state = observers(target, type);
   let listeners = state.slice();
-  let index = 0;
   let count = listeners.length;
+  let index = 0;
 
   // If error event and there are no handlers then print error message
   // into a console.
-  if (count === 0 && type === 'error') console.exception(message);
+  if (count === 0 && type === 'error') console.exception(args[0]);
   while (index < count) {
     try {
       let listener = listeners[index];
       // Dispatch only if listener is still registered.
-      if (~state.indexOf(listener)) yield listener.apply(target, args);
+      if (~state.indexOf(listener))
+        listener.apply(target, args);
     }
     catch (error) {
       // If exception is not thrown by a error listener and error listener is
@@ -115,8 +99,10 @@ emit.lazy = function lazy(target, type, message /*, ...*/) {
       if (type !== 'error') emit(target, 'error', error);
       else console.exception(error);
     }
-    index = index + 1;
+    index++;
   }
+   // Also emit on `"*"` so that one could listen for all events.
+  if (type !== '*') emit(target, '*', type, ...args);
 }
 exports.emit = emit;
 
@@ -145,7 +131,7 @@ function off(target, type, listener) {
   }
   else if (length === 1) {
     let listeners = event(target);
-    Object.keys(listeners).forEach(function(type) delete listeners[type]);
+    Object.keys(listeners).forEach(type => delete listeners[type]);
   }
 }
 exports.off = off;
@@ -171,7 +157,7 @@ exports.count = count;
  *    Dictionary of listeners.
  */
 function setListeners(target, listeners) {
-  Object.keys(listeners || {}).forEach(function onEach(key) {
+  Object.keys(listeners || {}).forEach(key => {
     let match = EVENT_TYPE_PATTERN.exec(key);
     let type = match && match[1].toLowerCase();
     let listener = listeners[key];
diff --git a/addon-sdk/source/lib/sdk/notifications.js b/addon-sdk/source/lib/sdk/notifications.js
index 0cf1885b74b..362f2858617 100644
--- a/addon-sdk/source/lib/sdk/notifications.js
+++ b/addon-sdk/source/lib/sdk/notifications.js
@@ -11,6 +11,10 @@ module.metadata = {
 const { Cc, Ci, Cr } = require("chrome");
 const apiUtils = require("./deprecated/api-utils");
 const errors = require("./deprecated/errors");
+const { isString, isUndefined, instanceOf } = require('./lang/type');
+const { URL } = require('./url');
+
+const NOTIFICATION_DIRECTIONS  = ["auto", "ltr", "rtl"];
 
 try {
   let alertServ = Cc["@mozilla.org/alerts-service;1"].
@@ -36,7 +40,7 @@ exports.notify = function notifications_notify(options) {
   };
   function notifyWithOpts(notifyFn) {
     notifyFn(valOpts.iconURL, valOpts.title, valOpts.text, !!clickObserver,
-             valOpts.data, clickObserver);
+             valOpts.data, clickObserver, valOpts.tag, valOpts.dir, valOpts.lang);
   }
   try {
     notifyWithOpts(notify);
@@ -66,15 +70,32 @@ function validateOptions(options) {
       is: ["string", "undefined"]
     },
     iconURL: {
-      is: ["string", "undefined"]
+      is: ["string", "undefined", "object"],
+      ok: function(value) {
+        return isUndefined(value) || isString(value) || (value instanceof URL);
+      },
+      msg: "`iconURL` must be a string or an URL instance."
     },
     onClick: {
       is: ["function", "undefined"]
     },
     text: {
-      is: ["string", "undefined"]
+      is: ["string", "undefined", "number"]
     },
     title: {
+      is: ["string", "undefined", "number"]
+    },
+    tag: {
+      is: ["string", "undefined", "number"]
+    },
+    dir: {
+      is: ["string", "undefined"],
+      ok: function(value) {
+        return isUndefined(value) || ~NOTIFICATION_DIRECTIONS.indexOf(value);
+      },
+      msg: '`dir` option must be one of: "auto", "ltr" or "rtl".'
+    },
+    lang: {
       is: ["string", "undefined"]
     }
   });
diff --git a/addon-sdk/source/lib/sdk/page-mod.js b/addon-sdk/source/lib/sdk/page-mod.js
index e6fd4c185d9..dd445c1e82f 100644
--- a/addon-sdk/source/lib/sdk/page-mod.js
+++ b/addon-sdk/source/lib/sdk/page-mod.js
@@ -136,18 +136,18 @@ const PageMod = Loader.compose(EventEmitter, {
 
   _applyOnExistingDocuments: function _applyOnExistingDocuments() {
     let mod = this;
-    // Returns true if the tab match one rule
-    let tabs = getAllTabs().filter(function (tab) {
-      return mod.include.matchesAny(getTabURI(tab));
-    });
+    let tabs = getAllTabs();
 
     tabs.forEach(function (tab) {
       // Fake a newly created document
       let window = getTabContentWindow(tab);
-      if (has(mod.attachTo, "top"))
+      if (has(mod.attachTo, "top") && mod.include.matchesAny(getTabURI(tab)))
         mod._onContent(window);
-      if (has(mod.attachTo, "frame"))
-        getFrames(window).forEach(mod._onContent);
+      if (has(mod.attachTo, "frame")) {
+        getFrames(window).
+            filter((iframe) => mod.include.matchesAny(iframe.location.href)).
+            forEach(mod._onContent);
+      }
     });
   },
 
diff --git a/addon-sdk/source/lib/sdk/request.js b/addon-sdk/source/lib/sdk/request.js
index 932deed9d37..ccf9bfb0342 100644
--- a/addon-sdk/source/lib/sdk/request.js
+++ b/addon-sdk/source/lib/sdk/request.js
@@ -130,6 +130,10 @@ const Request = Class({
     request(this).contentType = validateSingleOption('contentType', value);
   },
   get response() { return request(this).response; },
+  delete: function() {
+    runRequest('DELETE', this);
+    return this;
+  },
   get: function() {
     runRequest('GET', this);
     return this;
diff --git a/addon-sdk/source/lib/sdk/tabs/tab-fennec.js b/addon-sdk/source/lib/sdk/tabs/tab-fennec.js
index 70a7659beb6..1beb9c8a86e 100644
--- a/addon-sdk/source/lib/sdk/tabs/tab-fennec.js
+++ b/addon-sdk/source/lib/sdk/tabs/tab-fennec.js
@@ -13,6 +13,7 @@ const { activateTab, getTabTitle, setTabTitle, closeTab, getTabURL, getTabConten
 const { emit } = require('../event/core');
 const { getOwnerWindow: getPBOwnerWindow } = require('../private-browsing/window/utils');
 const { when: unload } = require('../system/unload');
+const { viewFor } = require('../event/core');
 const { EVENTS } = require('./events');
 
 const ERR_FENNEC_MSG = 'This method is not yet supported by Fennec';
@@ -33,7 +34,7 @@ const Tab = Class({
     // TabReady
     let onReady = tabInternals.onReady = onTabReady.bind(this);
     tab.browser.addEventListener(EVENTS.ready.dom, onReady, false);
-    
+
     let onPageShow = tabInternals.onPageShow = onTabPageShow.bind(this);
     tab.browser.addEventListener(EVENTS.pageshow.dom, onPageShow, false);
 
@@ -176,6 +177,10 @@ const Tab = Class({
 });
 exports.Tab = Tab;
 
+// Implement `viewFor` polymorphic function for the Tab
+// instances.
+viewFor.define(Tab, x => tabNS(x).tab);
+
 function cleanupTab(tab) {
   let tabInternals = tabNS(tab);
   if (!tabInternals.tab)
diff --git a/addon-sdk/source/lib/sdk/tabs/tab-firefox.js b/addon-sdk/source/lib/sdk/tabs/tab-firefox.js
index 17043df33c6..7f26f6551ce 100644
--- a/addon-sdk/source/lib/sdk/tabs/tab-firefox.js
+++ b/addon-sdk/source/lib/sdk/tabs/tab-firefox.js
@@ -13,9 +13,10 @@ const { getFaviconURIForLocation } = require("../io/data");
 const { activateTab, getOwnerWindow, getBrowserForTab, getTabTitle, setTabTitle,
         getTabURL, setTabURL, getTabContentType, getTabId } = require('./utils');
 const { getOwnerWindow: getPBOwnerWindow } = require('../private-browsing/window/utils');
-const viewNS = require('sdk/core/namespace').ns();
-const { deprecateUsage } = require('sdk/util/deprecate');
-const { getURL } = require('sdk/url/utils');
+const viewNS = require('../core/namespace').ns();
+const { deprecateUsage } = require('../util/deprecate');
+const { getURL } = require('../url/utils');
+const { viewFor } = require('../view/core');
 
 // Array of the inner instances of all the wrapped tabs.
 const TABS = [];
@@ -64,6 +65,7 @@ const TabTrait = Trait.compose(EventEmitter, {
 
     viewNS(this._public).tab = this._tab;
     getPBOwnerWindow.implement(this._public, getChromeTab);
+    viewFor.implement(this._public, getTabView);
 
     // Add tabs to getURL method
     getURL.implement(this._public, (function (obj) this._public.url).bind(this));
@@ -97,7 +99,7 @@ const TabTrait = Trait.compose(EventEmitter, {
     if (event.target == this._contentDocument)
       this._emit(EVENTS.ready.name, this._public);
   },
-  
+
   /**
    * Internal listener that emits public event 'load' when the page of this
    * tab is loaded, for triggering on non-HTML content, bug #671305
@@ -272,6 +274,10 @@ function getChromeTab(tab) {
   return getOwnerWindow(viewNS(tab).tab);
 }
 
+// Implement `viewFor` polymorphic function for the Tab
+// instances.
+const getTabView = tab => viewNS(tab).tab;
+
 function Tab(options, existingOnly) {
   let chromeTab = options.tab;
   for each (let tab in TABS) {
diff --git a/addon-sdk/source/lib/sdk/view/core.js b/addon-sdk/source/lib/sdk/view/core.js
index 19a8c4a4c1f..b321e852782 100644
--- a/addon-sdk/source/lib/sdk/view/core.js
+++ b/addon-sdk/source/lib/sdk/view/core.js
@@ -16,13 +16,12 @@ var method = require("method/core");
 // it returns `null`. You can implement this method for
 // this type to define what the result should be for it.
 let getNodeView = method("getNodeView");
-getNodeView.define(function(value) {
-  if (value instanceof Ci.nsIDOMNode)
-    return value;
-  return null;
-});
-
+getNodeView.define(x =>
+                     x instanceof Ci.nsIDOMNode ? x :
+                     x instanceof Ci.nsIDOMWindow ? x :
+                     null);
 exports.getNodeView = getNodeView;
+exports.viewFor = getNodeView;
 
 let getActiveView = method("getActiveView");
 exports.getActiveView = getActiveView;
diff --git a/addon-sdk/source/lib/sdk/widget.js b/addon-sdk/source/lib/sdk/widget.js
index da37620db28..51023336dff 100644
--- a/addon-sdk/source/lib/sdk/widget.js
+++ b/addon-sdk/source/lib/sdk/widget.js
@@ -26,6 +26,8 @@ const ERR_CONTENT = "No content or contentURL property found. Widgets must "
                "position.",
       ERR_DESTROYED = "The widget has been destroyed and can no longer be used.";
 
+const INSERTION_PREF_ROOT = "extensions.sdk-widget-inserted.";
+
 // Supported events, mapping from DOM event names to our event names
 const EVENTS = {
   "click": "click",
@@ -33,6 +35,11 @@ const EVENTS = {
   "mouseout": "mouseout",
 };
 
+// In the Australis menu panel, normally widgets should be treated like
+// normal toolbarbuttons. If they're any wider than this margin, we'll
+// treat them as wide widgets instead, which fill up the width of the panel:
+const AUSTRALIS_PANEL_WIDE_WIDGET_CUTOFF = 70;
+
 const { validateOptions } = require("./deprecated/api-utils");
 const panels = require("./panel");
 const { EventEmitter, EventEmitterTrait } = require("./deprecated/events");
@@ -45,8 +52,8 @@ const { WindowTracker } = require("./deprecated/window-utils");
 const { isBrowser } = require("./window/utils");
 const { setTimeout } = require("./timers");
 const unload = require("./system/unload");
-const { uuid } = require("./util/uuid");
 const { getNodeView } = require("./view/core");
+const prefs = require('./preferences/service');
 
 // Data types definition
 const valid = {
@@ -215,6 +222,13 @@ let model = {
 
 };
 
+function saveInserted(widgetId) {
+  prefs.set(INSERTION_PREF_ROOT + widgetId, true);
+}
+
+function haveInserted(widgetId) {
+  return prefs.has(INSERTION_PREF_ROOT + widgetId);
+}
 
 /**
  * Main Widget class: entry point of the widget API
@@ -555,6 +569,9 @@ let browserManager = {
     let idx = this.items.indexOf(item);
     if (idx > -1)
       this.items.splice(idx, 1);
+  },
+  propagateCurrentset: function browserManager_propagateCurrentset(id, currentset) {
+    this.windows.forEach(function (w) w.doc.getElementById(id).setAttribute("currentset", currentset));
   }
 };
 
@@ -605,36 +622,14 @@ BrowserWindow.prototype = {
     if (this.window.CustomizableUI) {
       let placement = this.window.CustomizableUI.getPlacementOfWidget(node.id);
       if (!placement) {
+        if (haveInserted(node.id)) {
+          return;
+        }
         placement = {area: 'nav-bar', position: undefined};
+        saveInserted(node.id);
       }
       this.window.CustomizableUI.addWidgetToArea(node.id, placement.area, placement.position);
-
-      // Depending on when this gets called, we might be in the right place now. In that case,
-      // don't run the following code.
-      if (node.parentNode != palette) {
-        return;
-      }
-      // Otherwise, insert:
-      let container = this.doc.getElementById(placement.area);
-      if (container.customizationTarget) {
-        container = container.customizationTarget;
-      }
-
-      if (placement.position !== undefined) {
-        // Find a position:
-        let items = this.window.CustomizableUI.getWidgetIdsInArea(placement.area);
-        let itemIndex = placement.position;
-        for (let l = items.length; itemIndex < l; itemIndex++) {
-          let realItems = container.getElementsByAttribute("id", items[itemIndex]);
-          if (realItems[0]) {
-            container.insertBefore(node, realItems[0]);
-            break;
-          }
-        }
-      }
-      if (node.parentNode != container) {
-        container.appendChild(node);
-      }
+      this.window.CustomizableUI.ensureWidgetPlacedInWindow(node.id, this.window);
       return;
     }
 
@@ -650,10 +645,14 @@ BrowserWindow.prototype = {
     }
 
     // if widget isn't in any toolbar, add it to the addon-bar
-    // TODO: we may want some "first-launch" module to do this only on very
-    // first execution
+    let needToPropagateCurrentset = false;
     if (!container) {
+      if (haveInserted(node.id)) {
+        return;
+      }
       container = this.doc.getElementById("addon-bar");
+      saveInserted(node.id);
+      needToPropagateCurrentset = true;
       // TODO: find a way to make the following code work when we use "cfx run":
       // http://mxr.mozilla.org/mozilla-central/source/browser/base/content/browser.js#8586
       // until then, force display of addon bar directly from sdk code
@@ -684,9 +683,11 @@ BrowserWindow.prototype = {
     // Otherwise, this code will collide with other instance of Widget module
     // during Firefox startup. See bug 685929.
     if (ids.indexOf(id) == -1) {
-      container.setAttribute("currentset", container.currentSet);
+      let set = container.currentSet;
+      container.setAttribute("currentset", set);
       // Save DOM attribute in order to save position on new window opened
       this.window.document.persist(container.id, "currentset");
+      browserManager.propagateCurrentset(container.id, set);
     }
   }
 }
@@ -736,7 +737,6 @@ WidgetChrome.prototype.update = function WC_update(updatedItem, property, value)
 WidgetChrome.prototype._createNode = function WC__createNode() {
   // XUL element container for widget
   let node = this._doc.createElement("toolbaritem");
-  let guid = String(uuid());
 
   // Temporary work around require("self") failing on unit-test execution ...
   let jetpackID = "testID";
@@ -753,6 +753,14 @@ WidgetChrome.prototype._createNode = function WC__createNode() {
   // Bug 626326: Prevent customize toolbar context menu to appear
   node.setAttribute("context", "");
 
+  // For use in styling by the browser
+  node.setAttribute("sdkstylewidget", "true");
+  // Mark wide widgets as such:
+  if (this.window.CustomizableUI &&
+      this._widget.width > AUSTRALIS_PANEL_WIDE_WIDGET_CUTOFF) {
+    node.classList.add("panel-wide-item");
+  }
+
   // TODO move into a stylesheet, configurable by consumers.
   // Either widget.style, exposing the style object, or a URL
   // (eg, can load local stylesheet file).
@@ -784,6 +792,13 @@ WidgetChrome.prototype.fill = function WC_fill() {
   // until the node is attached to a document.
   this.node.appendChild(iframe);
 
+  var label = this._doc.createElement("label");
+  label.setAttribute("value", this._widget.label);
+  label.className = "toolbarbutton-text";
+  label.setAttribute("crop", "right");
+  label.setAttribute("flex", "1");
+  this.node.appendChild(label);
+
   // add event handlers
   this.addEventHandlers();
 
diff --git a/addon-sdk/source/lib/sdk/window/browser.js b/addon-sdk/source/lib/sdk/window/browser.js
index 515db0ca752..3ceb9f12453 100644
--- a/addon-sdk/source/lib/sdk/window/browser.js
+++ b/addon-sdk/source/lib/sdk/window/browser.js
@@ -12,6 +12,7 @@ const unload = require('../system/unload');
 const { isWindowPrivate } = require('../window/utils');
 const { EventTarget } = require('../event/target');
 const { getOwnerWindow: getPBOwnerWindow } = require('../private-browsing/window/utils');
+const { viewFor } = require('../view/core');
 const { deprecateUsage } = require('../util/deprecate');
 
 const ERR_FENNEC_MSG = 'This method is not yet supported by Fennec, consider using require("sdk/tabs") instead';
@@ -48,6 +49,7 @@ const BrowserWindow = Class({
 });
 exports.BrowserWindow = BrowserWindow;
 
-getPBOwnerWindow.define(BrowserWindow, function(window) {
-  return windowNS(window).window;
-});
+const getWindowView = window => windowNS(window).window;
+
+getPBOwnerWindow.define(BrowserWindow, getWindowView);
+viewFor.define(BrowserWindow, getWindowView);
diff --git a/addon-sdk/source/lib/sdk/windows/firefox.js b/addon-sdk/source/lib/sdk/windows/firefox.js
index 27196fa8542..19f391f8e90 100644
--- a/addon-sdk/source/lib/sdk/windows/firefox.js
+++ b/addon-sdk/source/lib/sdk/windows/firefox.js
@@ -22,6 +22,7 @@ const { Cc, Ci, Cr } = require('chrome'),
 const { windowNS } = require('../window/namespace');
 const { isPrivateBrowsingSupported } = require('../self');
 const { ignoreWindow } = require('sdk/private-browsing/utils');
+const { viewFor } = require('../view/core');
 
 /**
  * Window trait composes safe wrappers for browser window that are E10S
@@ -76,6 +77,7 @@ const BrowserWindowTrait = Trait.compose(
 
       windowNS(this._public).window = this._window;
       getOwnerWindow.implement(this._public, getChromeWindow);
+      viewFor.implement(this._public, getChromeWindow);
 
       return this;
     },
@@ -84,6 +86,7 @@ const BrowserWindowTrait = Trait.compose(
     _onLoad: function() {
       try {
         this._initWindowTabTracker();
+        this._loaded = true;
       }
       catch(e) {
         this._emit('error', e);
@@ -94,9 +97,12 @@ const BrowserWindowTrait = Trait.compose(
     _onUnload: function() {
       if (!this._window)
         return;
-      this._destroyWindowTabTracker();
+      if (this._loaded)
+        this._destroyWindowTabTracker();
+
       this._emitOnObject(browserWindows, 'close', this._public);
       this._window = null;
+      windowNS(this._public).window = null;
       // Removing reference from the windows array.
       windows.splice(windows.indexOf(this), 1);
       this._removeAllListeners();
diff --git a/addon-sdk/source/lib/sdk/worker/utils.js b/addon-sdk/source/lib/sdk/worker/utils.js
index 6363abc8e87..2b53d3529b2 100644
--- a/addon-sdk/source/lib/sdk/worker/utils.js
+++ b/addon-sdk/source/lib/sdk/worker/utils.js
@@ -76,9 +76,6 @@ function Worker(options) {
   ["pageshow", "pagehide", "detach", "message", "error"].forEach(function(key) {
     trait.on(key, function() {
       emit.apply(emit, [worker, key].concat(Array.slice(arguments)));
-      // Workaround lack of ability to listen on all events by emulating
-      // such ability. This will become obsolete once Bug 821065 is fixed.
-      emit.apply(emit, [worker, "*", key].concat(Array.slice(arguments)));
     });
   });
   traits.set(worker, trait);
diff --git a/addon-sdk/source/test/fixtures/test-contentScriptFile.js b/addon-sdk/source/test/fixtures/test-contentScriptFile.js
new file mode 100644
index 00000000000..7dc0e3f2425
--- /dev/null
+++ b/addon-sdk/source/test/fixtures/test-contentScriptFile.js
@@ -0,0 +1,5 @@
+/* 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/. */
+
+self.postMessage("msg from contentScriptFile");
diff --git a/addon-sdk/source/test/test-content-events.js b/addon-sdk/source/test/test-content-events.js
index 9ec694f2530..dd0bbf91f66 100644
--- a/addon-sdk/source/test/test-content-events.js
+++ b/addon-sdk/source/test/test-content-events.js
@@ -44,16 +44,9 @@ exports["test multiple tabs"] = function(assert, done) {
 
   on(events, "data", handler);
   function handler ({type, target, timeStamp}) {
-    // ignore about:blank pages and *-document-global-created
-    // events that are not very consistent.
-    // ignore http:// requests, as Fennec's `about:home` page
-    // displays add-ons a user could install
-    if (target.URL !== "about:blank" &&
-        target.URL !== "about:home" &&
-        !target.URL.match(/^https?:\/\//i) &&
-        type !== "chrome-document-global-created" &&
-        type !== "content-document-global-created")
+    eventFilter(type, target, () => {
       actual.push(type + " -> " + target.URL)
+    });
   }
 
   let window = getMostRecentBrowserWindow();
@@ -92,12 +85,9 @@ exports["test nested frames"] = function(assert, done) {
   let actual = [];
   on(events, "data", handler);
   function handler ({type, target, timeStamp}) {
-    // ignore about:blank pages and *-global-created
-    // events that are not very consistent.
-    if (target.URL !== "about:blank" &&
-       type !== "chrome-document-global-created" &&
-       type !== "content-document-global-created")
+    eventFilter(type, target, () => {
       actual.push(type + " -> " + target.URL)
+    });
   }
 
   let window =  getMostRecentBrowserWindow();
@@ -126,4 +116,20 @@ exports["test nested frames"] = function(assert, done) {
     });
 };
 
+// ignore about:blank pages and *-document-global-created
+// events that are not very consistent.
+// ignore http:// requests, as Fennec's `about:home` page
+// displays add-ons a user could install
+// ignore local `searchplugins` files loaded
+// Calls callback if passes filter
+function eventFilter (type, target, callback) {
+  if (target.URL !== "about:blank" &&
+    target.URL !== "about:home" &&
+    !target.URL.match(/^https?:\/\//i) &&
+    !target.URL.match(/searchplugins/) &&
+    type !== "chrome-document-global-created" &&
+    type !== "content-document-global-created")
+  
+    callback();
+}
 require("test").run(exports);
diff --git a/addon-sdk/source/test/test-content-loader.js b/addon-sdk/source/test/test-content-loader.js
index 5690369fee2..7bd455b9776 100644
--- a/addon-sdk/source/test/test-content-loader.js
+++ b/addon-sdk/source/test/test-content-loader.js
@@ -6,6 +6,7 @@
 const { Loader } = require('sdk/content/loader');
 const self = require("sdk/self");
 const fixtures = require("./fixtures");
+const { URL } = require('sdk/url');
 
 exports['test:contentURL'] = function(assert) {
   let loader = Loader(),
@@ -204,6 +205,28 @@ exports['test:contentScriptFile'] = function(assert) {
     );
   }
 
+  let data = 'data:text/html,test';
+  try {
+    loader.contentScriptFile = [ { toString: () => data } ];
+    test.fail('must throw when non-URL object is set');
+  } catch(e) {
+    assert.equal(
+      'The `contentScriptFile` option must be a local URL or an array of URLs.',
+      e.message
+    );
+  }
+
+  loader.contentScriptFile = new URL(data);
+  assert.ok(
+    loader.contentScriptFile instanceof URL,
+    'must be able to set `contentScriptFile` to an instance of URL'
+  );
+  assert.equal(
+    data, 
+    loader.contentScriptFile.toString(),
+    'setting `contentScriptFile` to an instance of URL should preserve the url'
+  );
+
   loader.contentScriptFile = undefined;
   assert.equal(
     null,
diff --git a/addon-sdk/source/test/test-content-worker.js b/addon-sdk/source/test/test-content-worker.js
index 2fa8d9621f9..152c5803da9 100644
--- a/addon-sdk/source/test/test-content-worker.js
+++ b/addon-sdk/source/test/test-content-worker.js
@@ -17,6 +17,10 @@ const { LoaderWithHookedConsole } = require("sdk/test/loader");
 const { Worker } = require("sdk/content/worker");
 const { close } = require("sdk/window/helpers");
 const { set: setPref } = require("sdk/preferences/service");
+const { isArray } = require("sdk/lang/type");
+const { URL } = require('sdk/url');
+const fixtures = require("./fixtures");
+
 const DEPRECATE_PREF = "devtools.errorconsole.deprecation_warnings";
 
 const DEFAULT_CONTENT_URL = "data:text/html;charset=utf-8,foo";
@@ -396,8 +400,116 @@ exports["test:ensure console.xxx works in cs"] = WorkerTest(
   }
 );
 
+exports["test:setTimeout works with string argument"] = WorkerTest(
+  "data:text/html;charset=utf-8,<script>var docVal=5;</script>",
+  function(assert, browser, done) {
+    let worker = Worker({
+      window: browser.contentWindow,
+      contentScript: "new " + function ContentScriptScope() {
+        // must use "window.scVal" instead of "var csVal"
+        // since we are inside ContentScriptScope function.
+        // i'm NOT putting code-in-string inside code-in-string </YO DAWG>
+        window.csVal = 13;
+        setTimeout("self.postMessage([" + 
+                      "csVal, " + 
+                      "window.docVal, " + 
+                      "'ContentWorker' in window, " + 
+                      "'UNWRAP_ACCESS_KEY' in window, " + 
+                      "'getProxyForObject' in window, " + 
+                    "])", 1);
+      },
+      contentScriptWhen: "ready",
+      onMessage: function([csVal, docVal, chrome1, chrome2, chrome3]) {
+        // test timer code is executed in the correct context
+        assert.equal(csVal, 13, "accessing content-script values");
+        assert.notEqual(docVal, 5, "can't access document values (directly)");
+        assert.ok(!chrome1 && !chrome2 && !chrome3, "nothing is leaked from chrome");
+        done();
+      }
+    });
+  }
+);
 
-exports["test:setTimeout can\"t be cancelled by content"] = WorkerTest(
+exports["test:setInterval works with string argument"] = WorkerTest(
+  DEFAULT_CONTENT_URL,
+  function(assert, browser, done) {
+    let count = 0;
+    let worker = Worker({
+      window: browser.contentWindow,
+      contentScript: "setInterval('self.postMessage(1)', 50)",
+      contentScriptWhen: "ready",
+      onMessage: function(one) {
+        count++;
+        assert.equal(one, 1, "got " + count + " message(s) from setInterval");
+        if (count >= 3) done();
+      }
+    });
+  }
+);
+
+exports["test:setInterval async Errors passed to .onError"] = WorkerTest(
+  DEFAULT_CONTENT_URL,
+  function(assert, browser, done) {
+    let count = 0;
+    let worker = Worker({
+      window: browser.contentWindow,
+      contentScript: "setInterval(() => { throw Error('ubik') }, 50)",
+      contentScriptWhen: "ready",
+      onError: function(err) {
+        count++;
+        assert.equal(err.message, "ubik", 
+            "error (corectly) propagated  " + count + " time(s)");
+        if (count >= 3) done();
+      }
+    });
+  }
+);
+
+exports["test:setTimeout throws array, passed to .onError"] = WorkerTest(
+  DEFAULT_CONTENT_URL,
+  function(assert, browser, done) {
+    let worker = Worker({
+      window: browser.contentWindow,
+      contentScript: "setTimeout(function() { throw ['array', 42] }, 1)",
+      contentScriptWhen: "ready",
+      onError: function(arr) {
+        assert.ok(isArray(arr), 
+            "the type of thrown/propagated object is array");
+        assert.ok(arr.length==2, 
+            "the propagated thrown array is the right length");
+        assert.equal(arr[1], 42, 
+            "element inside the thrown array correctly propagated");
+        done();
+      }
+    });
+  }
+);
+
+exports["test:setTimeout string arg with SyntaxError to .onError"] = WorkerTest(
+  DEFAULT_CONTENT_URL,
+  function(assert, browser, done) {
+    let worker = Worker({
+      window: browser.contentWindow,
+      contentScript: "setTimeout('syntax 123 error', 1)",
+      contentScriptWhen: "ready",
+      onError: function(err) {
+        assert.equal(err.name, "SyntaxError", 
+            "received SyntaxError thrown from bad code in string argument to setTimeout");
+        assert.ok('fileName' in err, 
+            "propagated SyntaxError contains a fileName property");
+        assert.ok('stack' in err, 
+            "propagated SyntaxError contains a stack property");
+        assert.equal(err.message, "missing ; before statement", 
+            "propagated SyntaxError has the correct (helpful) message");
+        assert.equal(err.lineNumber, 1, 
+            "propagated SyntaxError was thrown on the right lineNumber");
+        done();
+      }
+    });
+  }
+);
+
+exports["test:setTimeout can't be cancelled by content"] = WorkerTest(
   "data:text/html;charset=utf-8,<script>var documentValue=true;</script>",
   function(assert, browser, done) {
 
@@ -700,4 +812,21 @@ exports["test:global postMessage"] = WorkerTest(
   }
 );
 
+exports['test:conentScriptFile as URL instance'] = WorkerTest(
+  DEFAULT_CONTENT_URL,
+  function(assert, browser, done) {
+
+    let url = new URL(fixtures.url("test-contentScriptFile.js"));
+    let worker =  Worker({
+      window: browser.contentWindow,
+      contentScriptFile: url,
+      onMessage: function(msg) {
+        assert.equal(msg, "msg from contentScriptFile", 
+            "received a wrong message from contentScriptFile");
+        done();
+      }
+    });
+  }
+);
+
 require("test").run(exports);
diff --git a/addon-sdk/source/test/test-event-core.js b/addon-sdk/source/test/test-event-core.js
index 9102dec11b1..3e28147718e 100644
--- a/addon-sdk/source/test/test-event-core.js
+++ b/addon-sdk/source/test/test-event-core.js
@@ -222,23 +222,24 @@ exports['test count'] = function(assert) {
   assert.equal(count(target, 'foo'), 0, 'listeners unregistered');
 };
 
-exports['test emit.lazy'] = function(assert) {
-  let target = {}, boom = Error('boom!'), errors = [], actual = []
+exports['test listen to all events'] = function(assert) {
+  let actual = [];
+  let target = {};
 
-  on(target, 'error', function error(e) errors.push(e))
+  on(target, 'foo', message => actual.push(message));
+  on(target, '*', (type, ...message) => {
+    actual.push([type].concat(message));
+  });
+ 
+  emit(target, 'foo', 'hello');
+  assert.equal(actual[0], 'hello',
+    'non-wildcard listeners still work');
+  assert.deepEqual(actual[1], ['foo', 'hello'],
+    'wildcard listener called');
 
-  on(target, 'a', function() 1);
-  on(target, 'a', function() {});
-  on(target, 'a', function() 2);
-  on(target, 'a', function() { throw boom });
-  on(target, 'a', function() 3);
-
-  for each (let value in emit.lazy(target, 'a'))
-    actual.push(value);
-
-  assert.deepEqual(actual, [ 1, undefined, 2, 3 ],
-                   'all results were collected');
-  assert.deepEqual(errors, [ boom ], 'errors reporetd');
+  emit(target, 'bar', 'goodbye');
+  assert.deepEqual(actual[2], ['bar', 'goodbye'],
+    'wildcard listener called for unbound event name');
 };
 
 require('test').run(exports);
diff --git a/addon-sdk/source/test/test-event-utils.js b/addon-sdk/source/test/test-event-utils.js
index b0163600a29..1e3604aa730 100644
--- a/addon-sdk/source/test/test-event-utils.js
+++ b/addon-sdk/source/test/test-event-utils.js
@@ -5,7 +5,7 @@
 'use strict';
 
 const { on, emit } = require("sdk/event/core");
-const { filter, map, merge, expand } = require("sdk/event/utils");
+const { filter, map, merge, expand, pipe } = require("sdk/event/utils");
 const $ = require("./event/helpers");
 
 function isEven(x) !(x % 2)
@@ -163,7 +163,96 @@ exports["test expand"] = function(assert) {
 
   assert.deepEqual(actual, ["a1", "b1", "a2", "c1", "c2", "b2", "a3"],
                    "all inputs data merged into one");
-}
+};
 
+exports["test pipe"] = function (assert, done) {
+  let src = {};
+  let dest = {};
+  
+  let aneventCount = 0, multiargsCount = 0;
+  let wildcardCount = {};
+
+  on(dest, 'an-event', arg => {
+    assert.equal(arg, 'my-arg', 'piped argument to event');
+    ++aneventCount;
+    check();
+  });
+  on(dest, 'multiargs', (...data) => {
+    assert.equal(data[0], 'a', 'multiple arguments passed via pipe');
+    assert.equal(data[1], 'b', 'multiple arguments passed via pipe');
+    assert.equal(data[2], 'c', 'multiple arguments passed via pipe');
+    ++multiargsCount;
+    check();
+  });
+  
+  on(dest, '*', (name, ...data) => {
+    wildcardCount[name] = (wildcardCount[name] || 0) + 1;
+    if (name === 'multiargs') {
+      assert.equal(data[0], 'a', 'multiple arguments passed via pipe, wildcard');
+      assert.equal(data[1], 'b', 'multiple arguments passed via pipe, wildcard');
+      assert.equal(data[2], 'c', 'multiple arguments passed via pipe, wildcard');
+    }
+    if (name === 'an-event')
+      assert.equal(data[0], 'my-arg', 'argument passed via pipe, wildcard');
+    check();
+  });
+
+  pipe(src, dest);
+
+  for (let i = 0; i < 3; i++)
+    emit(src, 'an-event', 'my-arg');
+  
+  emit(src, 'multiargs', 'a', 'b', 'c');
+
+  function check () {
+    if (aneventCount === 3 && multiargsCount === 1 &&
+        wildcardCount['an-event'] === 3 && 
+        wildcardCount['multiargs'] === 1)
+      done();
+  }
+};
+
+exports["test pipe multiple targets"] = function (assert) {
+  let src1 = {};
+  let src2 = {};
+  let middle = {};
+  let dest = {};
+
+  pipe(src1, middle);
+  pipe(src2, middle);
+  pipe(middle, dest);
+
+  let middleFired = 0;
+  let destFired = 0;
+  let src1Fired = 0;
+  let src2Fired = 0;
+
+  on(src1, '*', () => src1Fired++);
+  on(src2, '*', () => src2Fired++);
+  on(middle, '*', () => middleFired++);
+  on(dest, '*', () => destFired++);
+
+  emit(src1, 'ev');
+  assert.equal(src1Fired, 1, 'event triggers in source in pipe chain');
+  assert.equal(middleFired, 1, 'event passes through the middle of pipe chain');
+  assert.equal(destFired, 1, 'event propagates to end of pipe chain');
+  assert.equal(src2Fired, 0, 'event does not fire on alternative chain routes');
+  
+  emit(src2, 'ev');
+  assert.equal(src2Fired, 1, 'event triggers in source in pipe chain');
+  assert.equal(middleFired, 2,
+    'event passes through the middle of pipe chain from different src');
+  assert.equal(destFired, 2,
+    'event propagates to end of pipe chain from different src');
+  assert.equal(src1Fired, 1, 'event does not fire on alternative chain routes');
+  
+  emit(middle, 'ev');
+  assert.equal(middleFired, 3,
+    'event triggers in source of pipe chain');
+  assert.equal(destFired, 3,
+    'event propagates to end of pipe chain from middle src');
+  assert.equal(src1Fired, 1, 'event does not fire on alternative chain routes');
+  assert.equal(src2Fired, 1, 'event does not fire on alternative chain routes');
+};
 
 require('test').run(exports);
diff --git a/addon-sdk/source/test/test-notifications.js b/addon-sdk/source/test/test-notifications.js
index 4d92d57f16d..d154e390740 100644
--- a/addon-sdk/source/test/test-notifications.js
+++ b/addon-sdk/source/test/test-notifications.js
@@ -24,6 +24,53 @@ exports.testOnClick = function (assert) {
   loader.unload();
 };
 
+exports['test:numbers and URLs in options'] = function(assert) {
+  let [loader] = makeLoader(module);
+  let notifs = loader.require('sdk/notifications');
+  let opts = {
+    title: 123,
+    text: 45678,
+    // must use in-loader `sdk/url` module for the validation type check to work
+    iconURL: loader.require('sdk/url').URL('data:image/png,blah')
+  };
+  try {
+    notifs.notify(opts);
+    assert.pass('using numbers and URLs in options works');
+  } catch (e) {
+    assert.fail('using numbers and URLs in options must not throw');
+  }
+  loader.unload();
+}
+
+exports['test:new tag, dir and lang options'] = function(assert) {
+  let [loader] = makeLoader(module);
+  let notifs = loader.require('sdk/notifications');
+  let opts = {
+    title: 'best',
+    tag: 'tagging',
+    lang: 'en'
+  };
+
+  try {
+    opts.dir = 'ttb';
+    notifs.notify(opts);
+    assert.fail('`dir` option must not accept TopToBottom direction.');
+  } catch (e) {
+    assert.equal(e.message, 
+      '`dir` option must be one of: "auto", "ltr" or "rtl".');
+  }
+
+  try {
+    opts.dir = 'rtl';
+    notifs.notify(opts);
+    assert.pass('`dir` option accepts "rtl" direction.');
+  } catch (e) {
+    assert.fail('`dir` option must accept "rtl" direction.');
+  }
+
+  loader.unload();
+}
+
 // Returns [loader, mockAlertService].
 function makeLoader(module) {
   let loader = Loader(module);
diff --git a/addon-sdk/source/test/test-page-mod.js b/addon-sdk/source/test/test-page-mod.js
index b17ffe8034b..6e494bcbd38 100644
--- a/addon-sdk/source/test/test-page-mod.js
+++ b/addon-sdk/source/test/test-page-mod.js
@@ -430,6 +430,50 @@ exports.testWorksWithExistingTabs = function(assert, done) {
   });
 };
 
+exports.testExistingFrameDoesntMatchInclude = function(assert, done) {
+  let iframeURL = 'data:text/html;charset=utf-8,UNIQUE-TEST-STRING-42';
+  let iframe = '<iframe src="' + iframeURL + '" />';
+  let url = 'data:text/html;charset=utf-8,' + encodeURIComponent(iframe);
+  tabs.open({
+    url: url,
+    onReady: function onReady(tab) {
+      let pagemod = new PageMod({
+        include: url,
+        attachTo: ['existing', 'frame'],
+        onAttach: function() {
+          assert.fail("Existing iframe URL doesn't match include, must not attach to anything");
+        }
+      });
+      timer.setTimeout(function() {
+        assert.pass("PageMod didn't attach to anything")
+        pagemod.destroy();
+        tab.close(done);
+      }, 250);
+    }
+  });
+};
+
+exports.testExistingOnlyFrameMatchesInclude = function(assert, done) {
+  let iframeURL = 'data:text/html;charset=utf-8,UNIQUE-TEST-STRING-43';
+  let iframe = '<iframe src="' + iframeURL + '" />';
+  let url = 'data:text/html;charset=utf-8,' + encodeURIComponent(iframe);
+  tabs.open({
+    url: url,
+    onReady: function onReady(tab) {
+      let pagemod = new PageMod({
+        include: iframeURL,
+        attachTo: ['existing', 'frame'],
+        onAttach: function(worker) {
+          assert.equal(iframeURL, worker.url, 
+              "PageMod attached to existing iframe when only it matches include rules");
+          pagemod.destroy();
+          tab.close(done);
+        }
+      });
+    }
+  });
+};
+
 exports.testTabWorkerOnMessage = function(assert, done) {
   let { browserWindows } = require("sdk/windows");
   let tabs = require("sdk/tabs");
diff --git a/addon-sdk/source/test/test-page-worker.js b/addon-sdk/source/test/test-page-worker.js
index dbdca227d0a..c60da3c4fda 100644
--- a/addon-sdk/source/test/test-page-worker.js
+++ b/addon-sdk/source/test/test-page-worker.js
@@ -245,15 +245,14 @@ exports.testMultipleOnMessageCallbacks = function(assert, done) {
   let page = Page({
     contentScript: "self.postMessage('')",
     contentScriptWhen: "end",
-    onMessage: function() count += 1
+    onMessage: () => count += 1
   });
-  page.on('message', function() count += 2);
-  page.on('message', function() count *= 3);
-  page.on('message', function()
+  page.on('message', () => count += 2);
+  page.on('message', () => count *= 3);
+  page.on('message', () =>
     assert.equal(count, 9, "All callbacks were called, in order."));
-  page.on('message', function() done());
-
-}
+  page.on('message', done);
+};
 
 exports.testLoadContentPage = function(assert, done) {
   let page = Page({
diff --git a/addon-sdk/source/test/test-request.js b/addon-sdk/source/test/test-request.js
index f465b7d6617..a18d86d9919 100644
--- a/addon-sdk/source/test/test-request.js
+++ b/addon-sdk/source/test/test-request.js
@@ -210,6 +210,27 @@ exports.testInvalidJSON = function (assert, done) {
   });
 };
 
+exports.testDelete = function (assert, done) {
+  let srv = startServerAsync(port, basePath);
+
+  srv.registerPathHandler("/test-delete",
+      function handle(request, response) {
+    response.setHeader("Content-Type", "text/plain", false);
+  });
+
+  Request({
+    url: "http://localhost:" + port + "/test-delete",
+    onComplete: function (response) {
+      // We cannot access the METHOD of the request to verify it's set
+      // correctly.
+      assert.equal(response.text, "");
+      assert.equal(response.statusText, "OK");
+      assert.equal(response.headers["Content-Type"], "text/plain");
+      srv.stop(done);
+    }
+  }).delete();
+};
+
 exports.testHead = function (assert, done) {
   let srv = startServerAsync(port, basePath);
 
diff --git a/addon-sdk/source/test/test-simple-prefs.js b/addon-sdk/source/test/test-simple-prefs.js
index 83fd3e5b3e1..f1dfb97a746 100644
--- a/addon-sdk/source/test/test-simple-prefs.js
+++ b/addon-sdk/source/test/test-simple-prefs.js
@@ -41,7 +41,7 @@ exports.testSetGetBool = function(assert) {
 };
 
 // TEST: setting and getting preferences with special characters work
-exports.testSpecialChars = function(assert) {
+exports.testSpecialChars = function(assert, done) {
   let chars = specialChars.split("");
   let len = chars.length;
 
@@ -54,7 +54,7 @@ exports.testSpecialChars = function(assert) {
 
       // end test
       if (++count == len)
-        test.done();
+        done();
     })
     sp[char] = rand;
   });
diff --git a/addon-sdk/source/test/test-tab.js b/addon-sdk/source/test/test-tab.js
index fd7f1b088e5..0632c270793 100644
--- a/addon-sdk/source/test/test-tab.js
+++ b/addon-sdk/source/test/test-tab.js
@@ -7,6 +7,8 @@ const tabs = require("sdk/tabs"); // From addon-kit
 const windowUtils = require("sdk/deprecated/window-utils");
 const { getTabForWindow } = require('sdk/tabs/helpers');
 const app = require("sdk/system/xul-app");
+const { viewFor } = require("sdk/view/core");
+const { getTabId } = require("sdk/tabs/utils");
 
 // The primary test tab
 var primaryTab;
@@ -136,4 +138,17 @@ exports["test behavior on close"] = function(assert, done) {
   });
 };
 
+exports["test viewFor(tab)"] = (assert, done) => {
+  tabs.once("open", tab => {
+    const view = viewFor(tab);
+    assert.ok(view, "view is returned");
+    assert.equal(getTabId(view), tab.id, "tab has a same id");
+
+    tab.close();
+    done();
+  });
+
+  tabs.open({ url: "about:mozilla" });
+}
+
 require("test").run(exports);
diff --git a/addon-sdk/source/test/test-widget.js b/addon-sdk/source/test/test-widget.js
index 9d54d39296c..c25bc1b5ee9 100644
--- a/addon-sdk/source/test/test-widget.js
+++ b/addon-sdk/source/test/test-widget.js
@@ -18,6 +18,7 @@ const self = require("sdk/self");
 const windowUtils = require("sdk/deprecated/window-utils");
 const { getMostRecentBrowserWindow } = require('sdk/window/utils');
 const { close } = require("sdk/window/helpers");
+const unload = require("sdk/system/unload");
 const fixtures = require("./fixtures");
 
 let jetpackID = "testID";
@@ -51,7 +52,7 @@ exports.testConstructor = function(assert, done) {
 
   // Test basic construct/destroy
   AddonsMgrListener.onInstalling();
-  let w = widgets.Widget({ id: "fooID", label: "foo", content: "bar" });
+  let w = widgets.Widget({ id: "basic-construct-destroy", label: "foo", content: "bar" });
   AddonsMgrListener.onInstalled();
   assert.equal(widgetCount(), widgetStartCount + 1, "panel has correct number of child elements after widget construction");
 
@@ -69,7 +70,7 @@ exports.testConstructor = function(assert, done) {
   let loader = Loader(module);
   let widgetsFromLoader = loader.require("sdk/widget");
   let widgetStartCount = widgetCount();
-  let w = widgetsFromLoader.Widget({ id: "fooID", label: "foo", content: "bar" });
+  let w = widgetsFromLoader.Widget({ id: "destroy-on-unload", label: "foo", content: "bar" });
   assert.equal(widgetCount(), widgetStartCount + 1, "widget has been correctly added");
   loader.unload();
   assert.equal(widgetCount(), widgetStartCount, "widget has been destroyed on module unload");
@@ -94,25 +95,25 @@ exports.testConstructor = function(assert, done) {
 
   // Test no content or image
   assert.throws(
-    function() widgets.Widget({id: "fooID", label: "foo"}),
+    function() widgets.Widget({id: "no-content-throws", label: "foo"}),
     /^No content or contentURL property found\. Widgets must have one or the other\.$/,
     "throws on no content");
 
   // Test empty content, no image
   assert.throws(
-    function() widgets.Widget({id:"fooID", label: "foo", content: ""}),
+    function() widgets.Widget({id:"empty-content-throws", label: "foo", content: ""}),
     /^No content or contentURL property found\. Widgets must have one or the other\.$/,
     "throws on empty content");
 
   // Test empty image, no content
   assert.throws(
-    function() widgets.Widget({id:"fooID", label: "foo", image: ""}),
+    function() widgets.Widget({id:"empty-image-throws", label: "foo", image: ""}),
     /^No content or contentURL property found\. Widgets must have one or the other\.$/,
     "throws on empty content");
 
   // Test empty content, empty image
   assert.throws(
-    function() widgets.Widget({id:"fooID", label: "foo", content: "", image: ""}),
+    function() widgets.Widget({id:"empty-image-and-content-throws", label: "foo", content: "", image: ""}),
     /^No content or contentURL property found. Widgets must have one or the other\.$/,
     "throws on empty content");
 
@@ -138,14 +139,14 @@ exports.testConstructor = function(assert, done) {
 
   // Test position restore on create/destroy/create
   // Create 3 ordered widgets
-  let w1 = widgets.Widget({id: "first", label:"first", content: "bar"});
-  let w2 = widgets.Widget({id: "second", label:"second", content: "bar"});
-  let w3 = widgets.Widget({id: "third", label:"third", content: "bar"});
+  let w1 = widgets.Widget({id: "position-first", label:"first", content: "bar"});
+  let w2 = widgets.Widget({id: "position-second", label:"second", content: "bar"});
+  let w3 = widgets.Widget({id: "position-third", label:"third", content: "bar"});
   // Remove the middle widget
   assert.equal(widgetNode(1).getAttribute("label"), "second", "second widget is the second widget inserted");
   w2.destroy();
   assert.equal(widgetNode(1).getAttribute("label"), "third", "second widget is removed, so second widget is now the third one");
-  w2 = widgets.Widget({id: "second", label:"second", content: "bar"});
+  w2 = widgets.Widget({id: "position-second", label:"second", content: "bar"});
   assert.equal(widgetNode(1).getAttribute("label"), "second", "second widget is created again, at the same location");
   // Cleanup this testcase
   AddonsMgrListener.onUninstalling();
@@ -160,14 +161,14 @@ exports.testConstructor = function(assert, done) {
     let anotherWidgetsInstance = loader.require("sdk/widget");
     assert.ok(container().collapsed, "UI is hidden when no widgets");
     AddonsMgrListener.onInstalling();
-    let w1 = widgets.Widget({id: "foo", label: "foo", content: "bar"});
+    let w1 = widgets.Widget({id: "ui-unhide", label: "foo", content: "bar"});
     // Ideally we would let AddonsMgrListener display the addon bar
     // But, for now, addon bar is immediatly displayed by sdk code
     // https://bugzilla.mozilla.org/show_bug.cgi?id=627484
     assert.ok(!container().collapsed, "UI is already visible when we just added the widget");
     AddonsMgrListener.onInstalled();
     assert.ok(!container().collapsed, "UI become visible when we notify AddonsMgrListener about end of addon installation");
-    let w2 = anotherWidgetsInstance.Widget({id: "bar", label: "bar", content: "foo"});
+    let w2 = anotherWidgetsInstance.Widget({id: "ui-stay-open", label: "bar", content: "foo"});
     assert.ok(!container().collapsed, "UI still visible when we add a second widget");
     AddonsMgrListener.onUninstalling();
     w1.destroy();
@@ -214,7 +215,7 @@ exports.testConstructor = function(assert, done) {
 
   // text widget
   tests.push(function testTextWidget() testSingleWidget({
-    id: "text",
+    id: "text-single",
     label: "text widget",
     content: "oh yeah",
     contentScript: "self.postMessage(document.body.innerHTML);",
@@ -278,7 +279,7 @@ exports.testConstructor = function(assert, done) {
 
   // event: onclick + content
   tests.push(function testOnclickEventContent() testSingleWidget({
-    id: "click",
+    id: "click-content",
     label: "click test widget - content",
     content: "<div id='me'>foo</div>",
     contentScript: "var evt = new MouseEvent('click', {button: 0});" +
@@ -293,7 +294,7 @@ exports.testConstructor = function(assert, done) {
 
   // event: onmouseover + content
   tests.push(function testOnmouseoverEventContent() testSingleWidget({
-    id: "mouseover",
+    id: "mouseover-content",
     label: "mouseover test widget - content",
     content: "<div id='me'>foo</div>",
     contentScript: "var evt = new MouseEvent('mouseover'); " +
@@ -308,7 +309,7 @@ exports.testConstructor = function(assert, done) {
 
   // event: onmouseout + content
   tests.push(function testOnmouseoutEventContent() testSingleWidget({
-    id: "mouseout",
+    id: "mouseout-content",
     label: "mouseout test widget - content",
     content: "<div id='me'>foo</div>",
     contentScript: "var evt = new MouseEvent('mouseout');" +
@@ -323,7 +324,7 @@ exports.testConstructor = function(assert, done) {
 
   // event: onclick + image
   tests.push(function testOnclickEventImage() testSingleWidget({
-    id: "click",
+    id: "click-image",
     label: "click test widget - image",
     contentURL: fixtures.url("moz_favicon.ico"),
     contentScript: "var evt = new MouseEvent('click'); " +
@@ -338,7 +339,7 @@ exports.testConstructor = function(assert, done) {
 
   // event: onmouseover + image
   tests.push(function testOnmouseoverEventImage() testSingleWidget({
-    id: "mouseover",
+    id: "mouseover-image",
     label: "mouseover test widget - image",
     contentURL: fixtures.url("moz_favicon.ico"),
     contentScript: "var evt = new MouseEvent('mouseover');" +
@@ -353,7 +354,7 @@ exports.testConstructor = function(assert, done) {
 
   // event: onmouseout + image
   tests.push(function testOnmouseoutEventImage() testSingleWidget({
-    id: "mouseout",
+    id: "mouseout-image",
     label: "mouseout test widget - image",
     contentURL: fixtures.url("moz_favicon.ico"),
     contentScript: "var evt = new MouseEvent('mouseout'); " +
@@ -380,7 +381,7 @@ exports.testConstructor = function(assert, done) {
   // test updating widget content
   let loads = 0;
   tests.push(function testUpdatingWidgetContent() testSingleWidget({
-    id: "content",
+    id: "content-updating",
     label: "content update test widget",
     content: "<div id='me'>foo</div>",
     contentScript: "self.postMessage(1)",
@@ -403,7 +404,7 @@ exports.testConstructor = function(assert, done) {
   let url2 = "data:text/html;charset=utf-8,<body>nistel</body>";
 
   tests.push(function testUpdatingContentURL() testSingleWidget({
-    id: "content",
+    id: "content-url-updating",
     label: "content update test widget",
     contentURL: url1,
     contentScript: "self.postMessage(document.location.href);",
@@ -426,7 +427,7 @@ exports.testConstructor = function(assert, done) {
 
   // test tooltip
   tests.push(function testTooltip() testSingleWidget({
-    id: "text",
+    id: "text-with-tooltip",
     label: "text widget",
     content: "oh yeah",
     tooltip: "foo",
@@ -456,7 +457,7 @@ exports.testConstructor = function(assert, done) {
   // test updating widget tooltip
   let updated = false;
   tests.push(function testUpdatingTooltip() testSingleWidget({
-    id: "tooltip",
+    id: "tooltip-updating",
     label: "tooltip update test widget",
     tooltip: "foo",
     content: "<div id='me'>foo</div>",
@@ -472,7 +473,7 @@ exports.testConstructor = function(assert, done) {
 
   // test allow attribute
   tests.push(function testDefaultAllow() testSingleWidget({
-    id: "allow",
+    id: "allow-default",
     label: "allow.script attribute",
     content: "<script>document.title = 'ok';</script>",
     contentScript: "self.postMessage(document.title)",
@@ -484,7 +485,7 @@ exports.testConstructor = function(assert, done) {
   }));
 
   tests.push(function testExplicitAllow() testSingleWidget({
-    id: "allow",
+    id: "allow-explicit",
     label: "allow.script attribute",
     allow: {script: true},
     content: "<script>document.title = 'ok';</script>",
@@ -497,7 +498,7 @@ exports.testConstructor = function(assert, done) {
   }));
 
   tests.push(function testExplicitDisallow() testSingleWidget({
-    id: "allow",
+    id: "allow-explicit-disallow",
     label: "allow.script attribute",
     content: "<script>document.title = 'ok';</script>",
     allow: {script: false},
@@ -521,11 +522,11 @@ exports.testConstructor = function(assert, done) {
       function widgetCount2() container() ? container().querySelectorAll('[id^="widget\:"]').length : 0;
       let widgetStartCount2 = widgetCount2();
 
-      let w1Opts = {id:"first", label: "first widget", content: "first content"};
+      let w1Opts = {id:"first-multi-window", label: "first widget", content: "first content"};
       let w1 = testSingleWidget(w1Opts);
       assert.equal(widgetCount2(), widgetStartCount2 + 1, "2nd window has correct number of child elements after first widget");
 
-      let w2Opts = {id:"second", label: "second widget", content: "second content"};
+      let w2Opts = {id:"second-multi-window", label: "second widget", content: "second content"};
       let w2 = testSingleWidget(w2Opts);
       assert.equal(widgetCount2(), widgetStartCount2 + 2, "2nd window has correct number of child elements after second widget");
 
@@ -542,7 +543,7 @@ exports.testConstructor = function(assert, done) {
   tests.push(function testWindowClosing() {
     // 1/ Create a new widget
     let w1Opts = {
-      id:"first",
+      id:"first-win-closing",
       label: "first widget",
       content: "first content",
       contentScript: "self.port.on('event', function () self.port.emit('event'))"
@@ -595,7 +596,7 @@ exports.testConstructor = function(assert, done) {
     });
   });
 
-  if (!australis) {
+  if (false) {
     tests.push(function testAddonBarHide() {
       const tabBrowser = require("sdk/deprecated/tab-browser");
 
@@ -614,11 +615,13 @@ exports.testConstructor = function(assert, done) {
         assert.ok(container2().collapsed,
                   "2nd window starts with an hidden addon-bar");
 
-        let w1Opts = {id:"first", label: "first widget", content: "first content"};
+        let w1Opts = {id:"first-addonbar-hide", label: "first widget", content: "first content"};
         let w1 = testSingleWidget(w1Opts);
         assert.equal(widgetCount2(), widgetStartCount2 + 1,
                      "2nd window has correct number of child elements after" +
                      "widget creation");
+        assert.ok(!container().collapsed, "1st window has a visible addon-bar");
+        assert.ok(!container2().collapsed, "2nd window has a visible addon-bar");
         w1.destroy();
         assert.equal(widgetCount2(), widgetStartCount2,
                      "2nd window has correct number of child elements after" +
@@ -637,7 +640,7 @@ exports.testConstructor = function(assert, done) {
 
   // test widget.width
   tests.push(function testWidgetWidth() testSingleWidget({
-    id: "text",
+    id: "text-test-width",
     label: "test widget.width",
     content: "test width",
     width: 200,
@@ -661,7 +664,7 @@ exports.testConstructor = function(assert, done) {
   // test click handler not respond to right-click
   let clickCount = 0;
   tests.push(function testNoRightClick() testSingleWidget({
-    id: "click-content",
+    id: "right-click-content",
     label: "click test widget - content",
     content: "<div id='me'>foo</div>",
     contentScript: // Left click
@@ -762,7 +765,7 @@ exports.testWidgetMessaging = function testWidgetMessaging(assert, done) {
   let origMessage = "foo";
   const widgets = require("sdk/widget");
   let widget = widgets.Widget({
-    id: "foo",
+    id: "widget-messaging",
     label: "foo",
     content: "<bar>baz</bar>",
     contentScriptWhen: "end",
@@ -782,7 +785,7 @@ exports.testWidgetMessaging = function testWidgetMessaging(assert, done) {
 exports.testWidgetViews = function testWidgetViews(assert, done) {
   const widgets = require("sdk/widget");
   let widget = widgets.Widget({
-    id: "foo",
+    id: "widget-views",
     label: "foo",
     content: "<bar>baz</bar>",
     contentScriptWhen: "ready",
@@ -805,7 +808,7 @@ exports.testWidgetViewsUIEvents = function testWidgetViewsUIEvents(assert, done)
   const widgets = require("sdk/widget");
   let view = null;
   let widget = widgets.Widget({
-    id: "foo",
+    id: "widget-view-ui-events",
     label: "foo",
     content: "<div id='me'>foo</div>",
     contentScript: "var evt = new MouseEvent('click', {button: 0});" +
@@ -830,7 +833,7 @@ exports.testWidgetViewsUIEvents = function testWidgetViewsUIEvents(assert, done)
 exports.testWidgetViewsCustomEvents = function testWidgetViewsCustomEvents(assert, done) {
   const widgets = require("sdk/widget");
   let widget = widgets.Widget({
-    id: "foo",
+    id: "widget-view-custom-events",
     label: "foo",
     content: "<div id='me'>foo</div>",
     contentScript: "self.port.emit('event', 'ok');",
@@ -853,7 +856,7 @@ exports.testWidgetViewsTooltip = function testWidgetViewsTooltip(assert, done) {
   const widgets = require("sdk/widget");
 
   let widget = new widgets.Widget({
-    id: "foo",
+    id: "widget-views-tooltip",
     label: "foo",
     content: "foo"
   });
@@ -879,7 +882,7 @@ exports.testWidgetMove = function testWidgetMove(assert, done) {
   let gotFirstReady = false;
 
   let widget = widgets.Widget({
-    id: "foo",
+    id: "widget-move",
     label: label,
     content: "<bar>baz</bar>",
     contentScriptWhen: "ready",
@@ -947,7 +950,7 @@ exports.testWidgetWithPound = function testWidgetWithPound(assert, done) {
 
 exports.testContentScriptOptionsOption = function(assert, done) {
   let widget = require("sdk/widget").Widget({
-      id: "fooz",
+      id: "widget-script-options",
       label: "fooz",
       content: "fooz",
       contentScript: "self.postMessage( [typeof self.options.d, self.options] );",
@@ -1051,6 +1054,34 @@ exports.testSVGWidget = function(assert, done) {
   });
 };
 
+exports.testReinsertion = function(assert, done) {
+  const WIDGETID = "test-reinsertion";
+  let windowUtils = require("sdk/deprecated/window-utils");
+  let browserWindow = windowUtils.activeBrowserWindow;
+  let widget = require("sdk/widget").Widget({
+    id: "test-reinsertion",
+    label: "test reinsertion",
+    content: "Test",
+  });
+  let realWidgetId = "widget:" + jetpackID + "-" + WIDGETID;
+  // Remove the widget:
+  if (australis) {
+    browserWindow.CustomizableUI.removeWidgetFromArea(realWidgetId);
+  } else {
+    let widget = browserWindow.document.getElementById(realWidgetId);
+    let container = widget.parentNode;
+    container.currentSet = container.currentSet.replace("," + realWidgetId, "");
+    container.setAttribute("currentset", container.currentSet);
+    container.ownerDocument.persist(container.id, "currentset");
+  }
+
+  const tabBrowser = require("sdk/deprecated/tab-browser");
+  tabBrowser.addTab("about:blank", { inNewWindow: true, onLoad: function(e) {
+    assert.equal(e.target.defaultView.document.getElementById(realWidgetId), null);
+    close(e.target.defaultView).then(done);
+  }});
+};
+
 if (!australis) {
   exports.testNavigationBarWidgets = function testNavigationBarWidgets(assert, done) {
     let w1 = widgets.Widget({id: "1st", label: "1st widget", content: "1"});
diff --git a/addon-sdk/source/test/test-windows-common.js b/addon-sdk/source/test/test-windows-common.js
index 6ea2cbabbdb..0cc1f7d66c3 100644
--- a/addon-sdk/source/test/test-windows-common.js
+++ b/addon-sdk/source/test/test-windows-common.js
@@ -5,6 +5,9 @@
 
 const { Loader } = require('sdk/test/loader');
 const { browserWindows } = require('sdk/windows');
+const { viewFor } = require('sdk/view/core');
+const { Ci } = require("chrome");
+const { isBrowser, getWindowTitle } = require("sdk/window/utils");
 
 // TEST: browserWindows Iterator
 exports.testBrowserWindowsIterator = function(assert) {
@@ -55,4 +58,23 @@ exports.testWindowActivateMethod_simple = function(assert) {
                'Active tab is active after window.activate() call');
 };
 
+exports["test getView(window)"] = function(assert, done) {
+  browserWindows.once("open", window => {
+    const view = viewFor(window);
+
+    assert.ok(view instanceof Ci.nsIDOMWindow, "view is a window");
+    assert.ok(isBrowser(view), "view is a browser window");
+    assert.equal(getWindowTitle(view), window.title,
+                 "window has a right title");
+
+    window.close();
+    window.destroy();
+    assert.equal(viewFor(window), null, "window view is gone");
+    done();
+  });
+
+
+  browserWindows.open({ url: "data:text/html,<title>yo</title>" });
+};
+
 require('sdk/test').run(exports);