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Firefox Preview/GeckoView Add-ons Support

Back in June, Mozilla announced Firefox Preview, an early version of the new browser for Android that is built on top of Firefox’s own mobile browser engine, GeckoView. We’ve gotten great feedback about the superior performance of GeckoView so far. Not only is it faster than ever, it also opens up many opportunities for building deeper privacy features that we have already started exploring, and a lot of users were wondering what this step meant for add-ons.

We’re happy to confirm that GeckoView is currently building support for extensions through the WebExtensions API. This feature will be available in Firefox Preview, and we are looking forward to offering a great experience for both mobile users and developers.

Bringing GeckoView and Firefox Preview up to par with the APIs that were supported previously in Firefox for Android won’t happen overnight. For the remainder of 2019 and leading into 2020, we are focusing on building support for a selection of content from our Recommended Extensions program that work well on mobile and cover a variety of utilities and features.

At the moment, Firefox Preview does not yet officially support extensions. While some members of the community have discovered that some extensions inadvertently work in Firefox Preview, we do not recommend attempting to install them until they are officially supported as other issues may arise. We expect to implement support for the initial selection of extensions in the first half of 2020, and will post updates here as we make progress.

If you haven’t yet had a chance, why don’t you give Firefox Preview a try and let us know what you think.

10 comments on “Firefox Preview/GeckoView Add-ons Support”

  1. Andrew Ducker wrote on

    Great news!

    Will we be able to continue using the current Firefox on Mobile until then? I don’t want to lose my current addons in-between.

    1. Bleuarff wrote on

      Sure you can. Firefox preview is a separate application from the current Firefox. You absolutely can run them side-by-side without any problem.

  2. Lusito wrote on

    Great news!
    Any chance to get the list of recommended extensions you will focus on?
    I’d like to know if mine (forget me not) is one of them and if I can do anything to assist you in the process.

  3. Juraj Mäsiar wrote on

    “for the initial selection of extensions in the first half of 2020”
    🙁
    And here I was hoping it will be released with ESR 68 any day now with all existing Android API support…

    Also, what does it mean “initial selection of extensions”???
    Will I be able to install only some “verified” extensions due to security or some API will be missing and only some extensions will work?

    1. Sam Harrington wrote on

      “Will I be able to install only some “verified” extensions due to security or some API will be missing and only some extensions will work?”

      I read it as the latter: “Bringing GeckoView and Firefox Preview up to par with the APIs that were supported previously in Firefox for Android won’t happen overnight. “

    2. Juraj Mäsiar wrote on

      OK I see it’s the missing API :), sorry for not reading the article more carefully.
      Looking forward to see the first extensions-powered version!
      I really like the improved speed of current version.

  4. DG74 wrote on

    Please at least support Unlock Origin!
    Thank for your amazing work ☺️

  5. zakius wrote on

    mobile won’t suffer as much as desktop being limited to mere WE but anyway you should work on bringing back full power to users’ hands, not just chromium extensions

  6. Ryan wrote on

    Since two of your “Recommended Extensions” are Firefox Multi-Account Containers and Facebook Container, I *really* hope you will be supporting contextual identities in Fennec. This is even missing from mainline Firefox for Android, and is a huge privacy leak. Particularly with the “Chrome Pages” support that opens sites in a Firefox activity inside another app, I want to be confident that these are running in an isolated container without any access to cookies in my main profile, and which gets erased as soon as it is closed.

    1. Andy wrote on

      Great point, and I agree that this needs to happen. That being said, how big of a potential vulnerability is this? Aren’t most cookies for major sites encrypted nowadays? I would think that just because another app launches an instance of Firefox, it (the app launching it) wouldn’t be able to see much of what’s going on inside that instance, let alone encrypted content; however, I may be entirely wrong on this point.