Add-on Compatibility for Firefox 40

Firefox 40 will be released on August 11th. Here’s the list of changes that went into this version that can affect add-on compatibility. There is more information available in Firefox 40 for Developers, so you should also give it a look.

Extension signing

  • This is the first version of Firefox that will enforce our new signing requirements. All AMO add-ons have already been signed and we’re in the process of reviewing non-AMO add-ons. In this version, there’s a preference to disable the signing requirement (xpinstall.signatures.required), which will be removed in 41.




Please let me know in the comments if there’s anything missing or incorrect on these lists. If your add-on breaks on Firefox 40, I’d like to know.

The automatic compatibility validation and upgrade for add-ons on AMO will happen in the coming weeks, so keep an eye on your email if you have an add-on listed on our site with its compatibility set to Firefox 39.

17 comments on “Add-on Compatibility for Firefox 40”

  1. henry ng wrote on

    I have a problem with one of my addons. It was initially automatically signed, but after I updated the addon to 2.0.1, it doesn’t get signed automatically anymore.

    1. Jorge Villalobos wrote on

      New versions should be signed once they pass review. The “.1-signed” suffix was only added when we did the automatic signing of older versions. New ones keep their original version number.

  2. WildcatRay wrote on

    Is the EFF’s HTTPS Everywhere one of the non-AMO extensions under review? I hope it does not get aced out by the new signed addon requirement. Thanks.

  3. Michael Kaply wrote on

    Are there plans to move extension signing out a release if you can’t make it through the backlog of unlisted reviews?

    It wouldn’t be fair to add-on developers to turn this feature on if the reason all the add-ons stop working is because you can’t make it through the reviews…

    At what point are you going to cut off and say “You have to have submitted your unlisted add-on by this date to make sure it is reviewed by FF 40?

    1. Jorge Villalobos wrote on

      Yes, we are monitoring how we’re doing with unlisted reviews and pending fixes to the submission flow on AMO in order to make that call. It doesn’t necessarily mean that 40 won’t make it to Beta as-is, but it would stop the feature from making it to final release in 40.

      1. Mikoul Lhaboul wrote on

        What about the unbranded release since version 40 is almost here ?

        Also where we will find this unbranded release ?

        Thanks !

        1. Jorge Villalobos wrote on

          It’s not available yet. We’ll keep you posted about it on this blog. I suppose it’ll be available at least via FTP.

  4. rn10950 wrote on

    Is there a list of commonly used add-ons that used XPCOM?

    1. Jorge Villalobos wrote on

      If you mean binary XPCOM, I think there’s only one add-on on AMO that uses it and is still updated. Outside of AMO, many antivirus companion add-ons use it, and other popular ones do as well. There’s no public list, however.

  5. Ron wrote on

    You should send back copies of the signed version for add-ons hosted on AMO as well as add-ons not hosted on AMO as soon as they pass automated review. That way we can distribute them before they are reviewed to beta/cutting edge users. I assume you’re not doing this currently since I didn’t get back a copy, but I’m not sure when in the whole signing changeover I submitted it.

    1. Jorge Villalobos wrote on

      If your add-on passed automated review, you should have received an email with a link to a page where you can download it. Otherwise it might be still awaiting review and you’ll be notified when it is reviewed.

      1. Ron wrote on

        I’m still not sure I understand.

        Today(19 June 2015) I submitted several simple(under 10Kb) addons that only I will ever use to the unlisted area on AMO. I did receive emails so I can download the signed versions. I can also retrieve them from the developer hub > Manage My Submissions > [click on name of addon] > download the xpi and it is signed. Presumably these only had an automated review as I was able to download them right away.

        My question/suggestion is that I be able to do the same for my public addon (NewsFox My understanding from your answer is that this will be the case. It is not currently in my case as is not signed, but I see the submission was May 13 which may have preceeded the needed implementation. It passed the automated review, but is awaiting full review.

        On a related note(point me to the discussion if it exists), it would be nice to have a way for addons listed on AMO to have minor versions be signed without going through the full review if they pass automated review. Currently, we only release major versions on AMO, mostly to save the reviewers some time. With the current system this seems impossible to me. I know I can’t submit it as a new addon because the system will complain of duplicate UUID.

        1. Jorge Villalobos wrote on

          Listed add-ons on AMO will continue to have a manual code review because we need to ensure their quality on many fronts, which is essentially impossible to do automatically. If you want to avoid having to go through manual review all the time, it’s best to go unlisted.

          Having said that, there are some ideas we’re working on that should reduce review waiting times and maybe even allow you to skip review occasionally.

  6. Peter J. Sloetjes wrote on

    Newly-reviewed add-ons do not appear as signed on AMO, where previous versions did. That’s probably a temporal issue?

    1. Jorge Villalobos wrote on

      We only added the “.1-signed” suffix to the older versions that were automatically signed, due to technical reasons. New versions that are signed after review retain their original version number, but are still signed. You can verify that by downloading the XPI and uncompressing it. There should be a META-INF directory in it with the signature information.

  7. Kohei Yoshino wrote on

    Japanese translation is here:

    1. Jorge Villalobos wrote on

      Thank you!