--- a/browser/base/content/browser.js
+++ b/browser/base/content/browser.js
@@ -7429,23 +7429,16 @@ const gRemoteControl = {
     if (enabled) {
       mainWindow.setAttribute("remotecontrol", "true");
     } else {
       mainWindow.removeAttribute("remotecontrol");
     }
   },
 };
 
-function getNotificationBox(aWindow) {
-  var foundBrowser = gBrowser.getBrowserForDocument(aWindow.document);
-  if (foundBrowser)
-    return gBrowser.getNotificationBox(foundBrowser);
-  return null;
-}
-
 function getTabModalPromptBox(aWindow) {
   var foundBrowser = gBrowser.getBrowserForDocument(aWindow.document);
   if (foundBrowser)
     return gBrowser.getTabModalPromptBox(foundBrowser);
   return null;
 }
 
 /* DEPRECATED */