Add-on Compatibility for Firefox 45

Firefox 45 will be released on March 8th. Here’s the list of changes that went into this version that can affect add-on compatibility. There is more information available in Firefox 45 for Developers, so you should also give it a look.





  • Firefox is currently enforcing add-on signing, with a preference to override it. Firefox 46 will remove the preference entirely , which means your add-on will need to be signed in order to run in release versions of Firefox. You can read about your options here.


  • Support a simplified JSON add-on update protocol. Firefox now supports a JSON update file for add-ons that manage their own automatic updates, as an alternative to the existing XML format. For new add-ons, we suggest using the JSON format. You shouldn’t immediately switch for older add-ons until most of your users are on 45 and later.

Let me know in the comments if there’s anything missing or incorrect on these lists. If your add-on breaks on Firefox 45, 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 44.

7 comments on “Add-on Compatibility for Firefox 45”

  1. Kohei Yoshino wrote on

    Posted my Japanese translation:

    1. Jorge Villalobos wrote on


  2. john wrote on

    Wait, Firefox Panorama (one of it’s best unique features) is being REMOVED from Firefox?
    What’s going to happen to the 100+ tabs in other groups?

    1. Jorge Villalobos wrote on

      I think they are either collapsed into a single group or stored as bookmarks. The details are on this bug.

    2. Benjamin wrote on

      I’m pretty sure as long as you install “Tab Groups” by Quicksaver:

      before you update to firefox 45 (Or maybe even after) you will still have all your tab groups right where they belong.

      P.S. Quicksaver has a lot of neat addons, you may what to check out his other ones too!

  3. Cathy wrote on

    The new Firefox will not accept the Firefox Reminder add-on It says to contact you so you can verify it. Please do so I use this app every day! It’s bad enough I lost my other precious very much used “Cool Previews” and can’t find another one like it. Hey, maybe you guys could come up with something like it. I do a lot of research and I’m lost without it as well! Just a thought, but right now it’s the verification that is needed for Reminder Fox to work as an add-on with this new Firefox 44.0.2 Please help!

    1. Jorge Villalobos wrote on

      I’m not sure which add-on you’re referring to, but it is up to the developer to get it signed so Firefox will recognize it as verified. You should try contacting the add-on developer about this.