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.
Summary
The Tab
object represents a browser tab, and provides access to the browser
and the DOM content window hosted by that tab.
You access Tab
objects from the BrowserApp
object. BrowserApp
provides access to all tabs through its tabs
property, and to the currently selected tab through its selectedTab
property.
Properties
- id
- An identifier for this tab.
- browser
- The XUL
browser
object hosted by this tab. - window
- The DOM content window hosted by this tab.
Examples
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); }); }
This function retrieves the selected tab, then retrieves its browser
property, which it uses to log the current tab's session history:
function logSelectedTabHistory(window) { var tab = window.BrowserApp.selectedTab; var enumerator = tab.browser.sessionHistory.SHistoryEnumerator; while (enumerator.hasMoreElements()) { var historyEntry = enumerator.getNext().QueryInterface(Components.interfaces.nsIHistoryEntry); window.console.log(historyEntry.URI.spec); } }
If you want to retrieve the selected tab's URL, use this code:
var url = window.BrowserApp.selectedTab.browser.currentURI.spec;