This is an archived page. It's not actively maintained.

FUEL is deprecated as of Firefox 40. Consider using the Add-ons SDK instead

The FUEL Window object describes a browser window.

Method overview

fuelIBrowserTab open(in nsIURI aURI)


Attribute Type Description
tabs readonly attribute nsIVariant An array of browser tabs (fuelIBrowserTab) within the browser window. This array is a snapshot of the opened tabs, changes to the array don't affect the tabs in the browser. To manipulate tabs, use the fuelIWindow.open() method described on this page or various methods on fuelIBrowserTab
activeTab readonly attribute fuelIBrowserTab The currently-active tab within the browser window.
events readonly attribute fuelIEvents The events object for the browser window. supports: "TabOpen", "TabClose", "TabMove", "TabSelect"



Open a new browser tab, pointing to the specified URI.

fuelIBrowserTab open(
  in nsIURI aURI


The URI to load in the new browser tab.


This example sets up an event listener to watch for the "TabOpen" event, which is sent when a new tab is created, then opens a new window, loading the Mozilla web site into it. When the tab is created into which the Mozilla site is loaded, the onTabOpen() method in the example is called.

This demonstrates several useful techniques, including how to create a new tab in a window as well as how to obtain a reference to a newly-opened tab.

// Helper for making nsURI from string
function url(spec) {
  var ios = Components.classes["@mozilla.org/network/io-service;1"].getService(Components.interfaces.nsIIOService);
  return ios.newURI(spec, null, null);

function onTabOpen(event) {
  // Note that alert does not work, as the event gets called before the tab is loaded.
  var theTab = event.data.tab;    // Get the FUEL BrowserTab object for the tab
  Application.console.log("It opened");

var activeWin = Application.activeWindow;
activeWin.events.addListener("TabOpen", onTabOpen);

var browserTab = activeWin.open(url("http://mozilla.org"));

See also