WebExtensions in Firefox 45

In August we announced that work had begun on the WebExtensions API as the future of developing add-ons in Firefox. This post covers the progress we’ve made since then.

WebExtensions is currently in an alpha state, so while this is a great time to get involved, please keep in mind that things might change if you decide to use it in its current state. Since August, we’ve closed 77 bugs and ramped up the WebExtensions team at Mozilla. With the release of Firefox 45 in March 2016, we’ll have full support for the following APIs: alarms, contextMenus, pageAction and browserAction. Plus a bunch of partially supported APIs: bookmarks, cookies, extension, i18n, notifications, runtime, storage, tabs, webNavigation, webRequest, windows.

A full list of the API differences is available, and you can also follow along on the state of WebExtensions on arewewebextensionsyet.com. All add-ons built with WebExtensions are fully compatible with a multiprocess Firefox and will work in Chrome and Opera.

Beyond APIs, support is being added to addons.mozilla.org to enable developers to upload their add-ons and have them tested, that should be ready for Firefox 44. Documentation is being worked on in MDN and a set of example WebExtensions is available.

Over the coming months we will work our way towards a beta in Firefox 47 and the first stable release in Firefox 48. If you’d like to jump in to help, or get your API added, then please join us on our mailing list or at one of our public meetings.

Your contributions are appreciated!

17 comments on “WebExtensions in Firefox 45”

  1. Mindaugas wrote on

    I wanted to advertise a tool to analyse/convert chrome extensions: https://github.com/abarreir/crx2ff

    Disclosure: I have contributed some commits there during the past few days.

    1. Develra wrote on

      Very cool! Thanks for working on this

  2. Jackson wrote on

    Is there a place to see the differences between the Chrome extensions APIs and Web Extensions?

    While it’d be helpful for me to see API differences, at this point I’m mostly interested in vague feature differences. E.g. What does chrome support that Web Extensions will not support (the “Not Likely” tags on arewewebextensionsyet perhaps?) and what special features or APIs does Web Extensions bring (Access to toolbars or downloads or something? tab behavior modification? etc?)

    1. Andy McKay wrote on

      You can see the incompatibilities here: https://developer.mozilla.org/en-US/Add-ons/WebExtensions/Chrome_incompatibilities. We hope to bring more APIs to the browser than Chrome does and you can see some of those in the bugs.

  3. Q wrote on

    Will an extension like Tree Style Tab[1] be possible to convert to a WebExension? Something tells me it wont, and that scares the hell out of me.

    [1] https://addons.mozilla.org/en-US/firefox/addon/tree-style-tab/

    1. Andy McKay wrote on

      I would personally like to see that be a WebExtension. We are going to do more than Chrome does and tabs and sidebars are popular, let’s make something like that happen.

  4. Francis Kim wrote on

    Really looking forward to the March 2016 release!

  5. Chaofan Wu wrote on

    So Native Messaging will not be supported in Firefox 45?

  6. Chaofan Wu wrote on

    Is there any way to use dll when developing WebExtension in Firefox 45?

    1. Ping wrote on

      I have an urgent requirement to use js-ctype in extension.

      1. Chaofan Wu wrote on

        Thanks, heard of js-ctype but I wonder if it can be used in WebExtension.

  7. Shirley J. Carter wrote on

    This is not a comment, but Any could you p;ease tell me why I cannot get my book marks tool bar? Thwnk you so much, Shirley J. Carter

  8. Artem S. Tashkinov wrote on

    So, XUL is being deprecated, right?

    If that’s true, then welcome another Google Chrome clone with purely useless add-ons which allows only 5% of XUL features. And bid farewell to deep integration into the browser (off the top of my head, say good bye to NoScript, DownThemAll, ClassicThemRestorer, etc. etc. etc.)

    What an exciting browser … was.

    1. Andy McKay wrote on

      If you look at the bug tree for WebExtensions you’ll see that we’d like to support more APIs than Chrome. One of the bugs tracks how we’ll be getting one of your examples, NoScript, to work as a WebExtension.

    2. cadeyrn wrote on

      @Artem S. Tashkinov: see bug 1214733

  9. PJ wrote on

    Exciting? Not having extensions leak memory until FF crashes is plenty exciting for me, thank you very much.

  10. Vlas wrote on

    Does this mean that I can publish a web extension in add-ons store and others can install them without toggling any flags?