--- a/browser/base/content/test/alerts/head.js
+++ b/browser/base/content/test/alerts/head.js
@@ -1,29 +1,32 @@
 function promiseAlertWindow() {
   return new Promise(function(resolve) {
     let listener = {
       onOpenWindow(window) {
         let alertWindow = window.QueryInterface(Ci.nsIInterfaceRequestor).getInterface(Ci.nsIDOMWindow);
         alertWindow.addEventListener("load", function onLoad() {
           alertWindow.removeEventListener("load", onLoad);
           let windowType = alertWindow.document.documentElement.getAttribute("windowtype");
-          if (windowType == "alert:alert") {
-            Services.wm.removeListener(listener);
-            resolve(alertWindow);
+          if (windowType != "alert:alert") {
+            return;
           }
+          Services.wm.removeListener(listener);
+          resolve(alertWindow);
         });
       },
     };
     Services.wm.addListener(listener);
   });
 }
 
-// `promiseWindowClosed` is similar to `BrowserTestUtils.closeWindow`, but
-// doesn't call `window.close()`.
+/**
+ * Similar to `BrowserTestUtils.closeWindow`, but
+ * doesn't call `window.close()`.
+ */
 function promiseWindowClosed(window) {
   return new Promise(function(resolve) {
     Services.ww.registerNotification(function observer(subject, topic, data) {
       if (topic == "domwindowclosed" && subject == window) {
         Services.ww.unregisterNotification(observer);
         resolve();
       }
     });

--- a/browser/locales/en-US/chrome/browser/browser.properties
+++ b/browser/locales/en-US/chrome/browser/browser.properties
@@ -377,17 +377,19 @@ geolocation.shareWithFile2=Would you lik
 
 webNotifications.receiveForSession=Receive for this session
 webNotifications.receiveForSession.accesskey=s
 webNotifications.alwaysReceive=Always Receive Notifications
 webNotifications.alwaysReceive.accesskey=A
 webNotifications.neverShow=Always Block Notifications
 webNotifications.neverShow.accesskey=N
 webNotifications.receiveFromSite=Would you like to receive notifications from this site?
+# LOCALIZATION NOTE (webNotifications.upgradeTitle): When using native notifications on OS X, the title may be truncated around 32 characters.
 webNotifications.upgradeTitle=Upgraded notifications
+# LOCALIZATION NOTE (webNotifications.upgradeInfo): When using native notifications on OS X, the body may be truncated around 100 characters in some views.
 webNotifications.upgradeInfo=You will receive notifications from sites, even those not open in a tab. Click to learn more.
 
 # Pointer lock UI
 
 pointerLock.allow2=Hide pointer
 pointerLock.allow2.accesskey=H
 pointerLock.alwaysAllow=Always allow hiding
 pointerLock.alwaysAllow.accesskey=A