WebExtensions still on track for Firefox 48

Martin Brinkmann
Apr 30, 2016

WebExtensions, a new browser API for Firefox that Mozilla wants add-on developers to focus on once it has been released, is still on track for a Firefox 48 release.

Mozilla announced the push towards WebExtensions back in mid-2015 and made the decision back then to model the new API after Google's Blink extension API.

Mozilla has several reasons to develop a new API, including making it easier to port extensions from and to Google Chrome and Chromium-based web browsers, making the review process easier, and making add-ons more robust when it comes to browser updates.

The initial announcement raised fear that Firefox's superior add-on system would be severely limited with the release of WebExtensions since Mozilla announced that it would deprecate core features of the current system in the future as well.

WebExtensions Progress

The organization targets Firefox 48 for a first stable release of WebExtensions in the browser, and that goal has not changed yet.

Mozilla Engineering Manager Andy McKay revealed yesterday that WebExtensions are still on their way towards a Firefox 48 release.

He highlighted some of the progress that has been made by developers working on the implementation, and noted that the current state allowed an extensions such as Ghostery to be written as a web extension already.

In Firefox 48 we pushed hard to make the WebRequest API a solid foundation for privacy and security add-ons such as Ghostery, RequestPolicy and NoScript. With the current implementation of the onErrorOccurred function, it is now possible for Ghostery to be written as a WebExtension.

The first Firefox-only feature, reliable origin information, has been implemented as well which will benefit extensions such as uBlock Origin or NoScript when they are ported to the new API.

NoScript users on top of that will benefit from requestBody support which, according to McKay, will improve the performance of NoScript's XSS filter by the factor 20 or more in some cases.

WebExtensions in Firefox 48

firefox 48 web extensions

It is certainly the case that WebExtensions won't replicate all functionality of Firefox's add-on system with the initial Firefox 48 release.

If you look at the road map -- a draft currently -- you will notice that features won't land in Firefox 48.

  • Parity with Chrome's Extensions API.
  • Getting top 20 Chrome and Firefox add-ons to work with WebExtensions-
  • Release of native.js prototype which allows add-on developers to access XPCOM or XUL among other things. You can check out this article on native.js or the bug listing on Bugzilla. One idea behind the feature is to monitor the use closely to add popular features used to the WebExtensions API.

Mozilla landed a change recently that improves Chrome compatibility. Basically, it allows for Chrome extensions to be run in Firefox without manifest changes when they are loaded via about:debugging as temporary add-ons.

One interesting and ironic side-effect of Mozilla's WebExtensions implementation is that Firefox for Android users will be able to install (some) Chrome extensions in the web browser while Chrome users can't.

Firefox Nightly users who want to get a feel for WebExtensions can check out example extensions that Mozilla publishes on GitHub.

Firefox 48 will be released on August 2, 2016.

I'm cautiously optimistic about the implementation of WebExtensions. What about you?

WebExtensions still on track for Firefox 48
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WebExtensions still on track for Firefox 48
Mozilla revealed that WebExtensions, a new API for extensions in Firefox, is still on track for an initial Firefox 48 release later this year.
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  1. pHROZEN gHOST said on May 3, 2016 at 4:22 pm

    Firefox was the best browser at one time. Its flames are going to go out with v48.

    I can’t help but think that Mozilla is doing this on purpose. Did they sell out to Google?

  2. bystander said on May 3, 2016 at 7:23 am

    Ken Saunders, absolutely true.
    Even Ghostery (RIP) was not blocking cookies in Chrome while it did in Firefox. It’s been a few times I read something like “you can’t do it in Chromium” about some addons functionality (sorry, I can’t recall exactly what was it).
    Perhaps someday they will extend WebExtensions to the point where they once were with their current API. But until then…

    So there’s no way Chrome’s extensions are more functional as of today.
    I alter my browsers appearance and behavior the big way. I don’t want another Chrome.
    There’s no shortage of dedicated Firefox developers who like to extend Firefox and don’t care to write for Chrome at the same time. Firefox is all about customization. Deep, advanced customization, if you need one. Compromise that, and you lose your biggest advantage.

  3. Sohan said on May 2, 2016 at 5:56 am

    You can grumble all you can but we have to admit that Chrome has got more extensions than firefox and the extensions are better looking and better in functionality, if we dont evolve our tech then we cannot compete with Chrome. It is a hard truth which you have to accept

    1. Ken Saunders said on May 2, 2016 at 8:06 pm

      “Chrome has got more extensions than firefox…”
      Maybe, maybe not. If you include apps, then perhaps, but what they do have isn’t impressive. They don’t do much.

      “…the extensions are better looking and better in functionality”
      I don’t know what “better looking” means, but “better in functionality” is absolutely untrue.
      For now at least, Firefox add-ons can alter pretty much the entire UI and core functionality of Firefox.
      Chrome extensions cannot.

    2. Lestat said on May 2, 2016 at 12:01 pm

      And exactly that is the bad idea. You should not compete with Chrome.

      Competing with Chrome is equal like Opera with abandoning advanced users, which is already happening for gaining Chrome users, which will never move on that high in numbers as Mozilla wants.

      What are you, some Mozilla developer? In that case you clearly show the attitude why people are leaving. “We” have to compete with Chrome, so “we” have to replace “our” creation with “theirs”.

      If people would want to use Chrome they would. People expect Firefox, and that means Firefox customization built inside the browser, Firefox add-ons and Firefox themes, no Chrome nonsense which is way inferior to everything Mozilla has created in the past.

      Let Chrome be Chrome, you don’t need their users, the problem is you have alienated your power users, and the rest of them you will alienate with the upcoming changes.

      You had a good market share thanks to that kind of users, and you are to blame that they are moving on because you guys are jealous of Google’s massive user base. And for this you abandon all advanced users. Like Opera. They would come back if you would re-focus Firefox again towards power users or geeks instead of simple and Chrome users.

      You guys are a total lost cause.

    3. Ben said on May 2, 2016 at 11:40 am

      I could not even find a decent mouse gesture addon for Chrome.
      Additionally nearly every addon is packed with malware/spyware/donate-stuff.
      Chrome store is horrific.

    4. Sajadi said on May 2, 2016 at 8:59 am

      You are talking about web apps. They are different than the webextension system.

      Mozilla does not implement the apps system, they are adopting the extension system which offers only limited abilities what you are allowed to change.

      With the app system you can do something like Vivaldi, which is Chromium with a webapp on top of it which creates the UI and the features. That would be impossible with webextensions.

      So, sorry, you will not get the shiny ones with webextensions system.

  4. A41202813GMAIL said on May 1, 2016 at 8:26 pm

    I Just Hope Brand New **FEBE** And **OPEN IN CHROME** Versions Will Start Working For All The Major Browsers.


  5. wonton said on May 1, 2016 at 4:26 pm

    Most great addons developers abandon developing them due to all the crap mozilla has done just look at download them alll about:addons-memory there are so many addons dying each release these addons will never make it to webjunk next mozilla will sell firefox to google or merge firefox with chrome that 300 million must had some strings with it.

  6. anon said on May 1, 2016 at 10:42 am

    There’s a lot of negativity about WebExtensions due to misinformation and appeals to fear. Every software that starts from scratch always sucks at first. In 2 years, most people won’t notice the difference.

    1. Lestat said on May 1, 2016 at 2:46 pm

      Web Extensions ARE less powerful than XUL ones, no matter how many API Mozilla will add to them, they still will be less powerful than XUL.

      Only one thing to do once XUL is gone, adding Blink, and Mozilla’s long way to the dark Google side of things is done. They are already experimenting with Electron/Chromium. Of course they say it is UX tests only, but in Mozilla’s case, it is always good to not fully trust them.

      Anyway, many people will have no reason to use Firefox with Webextensions. And Mozilla will lose again tons of users, just wait and see.

      There is no good reason why Mozilla should add more Chrome compatibility to their browser. Firefox is NOT Chrome! So what is wrong with doing their own things instead of implementing the extension system of the competition. The only chance for Mozilla is to embrace again power users and value them higher than the typical computer rookie.

  7. TomW said on May 1, 2016 at 10:11 am

    At this point with firefox gutting all of its differentiating advantages there are less reasons to stick with it. I’ve already been experimenting with using Vivaldi as my primary browser over the past 2 weeks in preparation.

  8. gh said on May 1, 2016 at 7:01 am

    about the implementation of WebExtensions:

    the “embrace, extend, extinguish” agenda marches on…

  9. Earl said on May 1, 2016 at 1:30 am

    Given that quite a few extension developers have stated intentions not to develop anything further for Firefox, it’s a safe bet that many extensions will not be “compatible” with those future releases of Firefox. Some of these extensions are very popular ones. There may be a few Chrome devs who want to port to Firefox, but hardly enough for Mozilla to consider of value to them (except in their wildest, irrational dreams).

    Anyway, as Mozilla’s roadmap veers away from XUL/XPCOM, my roadmap veers away from future releases of Firefox. Pale Moon is still off in the boonies, where it will stay. Instead of using only Firefox, I’ll be using other browsers–only occasionally using Firefox, and when I do, it will almost surely be an older release. Mozilla deserves nothing more now than to fade away due to lack of interest and use.

  10. Dave said on April 30, 2016 at 11:48 pm

    This would never happen if the pitchforks hadn’t all been recycled.

    When XUL and XPCOM are removed, Firefox is gone.

  11. Henk van Setten said on April 30, 2016 at 3:18 pm

    I find this post a little vague about the consequences for existing add-ons in Firefox. Maybe that’s because Mozilla itself is vague about this, too?

    Especially for people who use a lot of less “common” add-ons, the two most obvious questions Mozilla needs to answer more clearly are:

    (1) Will this policy indeed cripple or disable many existing add-ons?
    (2) If so, at what point in time can we expect this to happen?

    This might decide whether some of today’s Firefox users will prefer a switch to its more conservative browser cousin, Pale Moon.

    1. Ben said on May 1, 2016 at 10:48 am

      > I find this post a little vague about the consequences for existing add-ons in Firefox.
      Simple. Every addon that does not use the API at the moment has to be re-written.
      This will disable all non-updated addons in the future.

      Additionally Mozilla will not add an API for everything addons can do now, so even if the addon author still wants to update the addon, he simply cannot do it anymore.

    2. Martin Brinkmann said on April 30, 2016 at 3:36 pm

      I think the main issue right now is that things are still being created on the API side, and that there is no full feature list that all Firefox extensions require so that they can be ported to WebExtensions.

      My best guess is that Mozilla will get Chrome parity first, which should cover x percent of all Firefox extensions, and on top of that, get the features working that the most popular Firefox extensions require as it delivers the biggest gain when it comes to users of the browser. This too should add another x percent of overall compatibility.

      Once that is done, Mozilla will improve the API regularly so that even more add-ons can be ported.

      I don’t think that we will get 100% compatibility though, but my best guess is that no one knows currently at what percentage things will end up at.

      So, it is likely that some extensions may never be compatible with WebExtensions.

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