MDN’s new design is in Beta! A sneak peek: https://blog.mozilla.org/opendesign/mdns-new-design-beta/

Add-ons using the techniques described in this document are considered a legacy technology in Firefox. Don't use these techniques to develop new add-ons. Use WebExtensions instead. If you maintain an add-on which uses the techniques described here, consider migrating it to use WebExtensions.

Starting from Firefox 53, no new legacy add-ons will be accepted on addons.mozilla.org (AMO) for desktop Firefox and Firefox for Android.

Starting from Firefox 57, WebExtensions will be the only supported extension type. Desktop Firefox and Firefox for Android will not load other extension types.

Even before Firefox 57, changes coming up in the Firefox platform will break many legacy extensions. These changes include multiprocess Firefox (e10s), sandboxing, and multiple content processes. Legacy extensions that are affected by these changes should migrate to WebExtensions if they can. See the "Compatibility Milestones" document for more information.

A wiki page containing resources, migration paths, office hours, and more, is available to help developers transition to the new technologies.

aThe BrowserApp object is only available to privileged code running on Firefox for Android, and is intended for use by Firefox for Android add-ons.

Summary

tabs is a property of the BrowserApp object. It is an Array of all currently open tabs, represented as Tab objects.

For example, this function retrieves the array of open tabs from BrowserApp, then fetches each tab's DOM content window, and logs the title of the DOM document loaded into the window:

function logTabTitles(window) {
  var tabs = window.BrowserApp.tabs;
  tabs.forEach(function(tab) {
    window.console.log(tab.window.document.title);
  });
}

Document Tags and Contributors

 Contributors to this page: rebloor, andrewtruongmoz, wbamberg, dkocho4, ethertank
 Last updated by: rebloor,