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.
From Firefox 53 onwards, no new legacy add-ons will be accepted on addons.mozilla.org (AMO).
From Firefox 57 onwards, WebExtensions will be the only supported extension type, and Firefox will not load other 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.
A wiki page containing resources, migration paths, office hours, and more, is available to help developers transition to the new technologies.
Firefox 35
Highlights
- Added access keys for context menu.
- Removed
isPrivateBrowsingfromBrowserWindow.
Details
GitHub commits made between Firefox 34 and Firefox 35. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 34 and Firefox 35. This will not include any uplifts made after this release entered Aurora.
Firefox 34
Highlights
- New API: dev/panel enables you to extend the Firefox Developer Tools.
- jpm beta released.
"./my-file"introduced everywhere as an alias forrequire("sdk/self").data.url("my-file")- Added the ability to attach stylesheets to individual tabs.
Details
GitHub commits made between Firefox 33 and Firefox 34. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 33 and Firefox 34. This will not include any uplifts made after this release entered Aurora.
Firefox 33
Highlights
- Added support for context menus in panels via a new option in the
Panelconstructor. - Added
tab.readyState. - Added a
BrowserWindowparameter tosidebar.show()andsidebar.hide(), to control the window for which the sidebar will be shown or hidden.
Details
GitHub commits made between Firefox 32 and Firefox 33. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 32 and Firefox 33. This will not include any uplifts made after this release entered Aurora.
Firefox 32
Highlights
- Added
excludeoption toPageMod. - Added
anonymousoption toRequest. - Add-on Debugger now includes a Console and a Scratchpad.
Details
GitHub commits made between Firefox 31 and Firefox 32. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 31 and Firefox 32. This will not include any uplifts made after this release entered Aurora.
Firefox 31
Highlights
- Add-on Debugger
- Added the ability to convert between high-level BrowserWindow objects and DOM windows, and between high-level Tab objects and XUL tabs.
- Updated the default theme used for panels on Mac OS X.
- Added contentStyle and contentStyleFile options to panel.
Details
GitHub commits made between Firefox 30 and Firefox 31. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 30 and Firefox 31. This will not include any uplifts made after this release entered Aurora.
Firefox 30
Highlights
- Added the ability to anchor panels to buttons.
- Changes in the way content scripts share objects with page scripts. Documentation and blog post.
- Added
child_process, an implementation of the node.js child_process API. - Content scripts in page-mod get
detachevents when the add-on is disabled or removed. throttle()anddebounce()functions added tolang/functional.getTabForId()function added totabs/utils.
Details
GitHub commits made between Firefox 29 and Firefox 30. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 29 and Firefox 30. This will not include any uplifts made after this release entered Aurora.
Firefox 29
Highlights
- Added new UI modules for Australis: ActionButton, ToggleButton, Frame and Toolbar.
- Made the preferences branch for simple-prefs configurable.
- Added
PredicateContextto sdk/context-menu. - Deprecated
widgetin favor of the new UI modules. - Removed tab-browser, app-strings and api-utils.publicConstructor
Details
GitHub commits made between Firefox 28 and Firefox 29. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 28 and Firefox 29. This will not include any uplifts made after this release entered Aurora.
Firefox 28
Highlights
- Added wildcard event type "*".
- Added a
readyevent to sidebars. - Added a
delete()method to sdk/request.
Details
GitHub commits made between Firefox 27 and Firefox 28. This will not include any uplifts made after this release entered Aurora.
Bugs fixed between Firefox 27 and Firefox 28. This will not include any uplifts made after this release entered Aurora.