Well, I just updated Firefox on Ubuntu 14 to v43 doing sudo apt-get update, and my old extensions stopped working as they are not signed. Mozilla has apparently stated that:


Installation of unsigned extensions will still be possible on Nightly and Developer Edition, as well as special, unbranded builds of Release and Beta that will be available mainly for developers testing their extensions.


The Nightly and Developer Editions of Firefox based on 42 and above will retain the preference to disable signing enforcement, allowing the development and/or use of unsigned add-ons in those versions. Unbranded versions of Firefox based on releases will also be made available for developers, and are expected to be in place for Firefox 42 for release (and potentially beta).

I don't want to install Nightly because I don't want to update every day; I don't want the developer version because it includes extra stuff I don't need. So, I wanted to try this "unbranded" Firefox build, which would apparently allow me to run unsigned extensions. But I'm looking everywhere for it, and I cannot find it. And Firefox 43 already landed, and (if I recall correctly), 43 > 42, so these "unbranded" builds should have already been available, no?

So, where can this unbranded Firefox be downloaded from? If it is not released yet, when will it be released?

  • cross-posted to support.mozilla.org/en-US/questions/1099617 – sdaau Dec 18 '15 at 6:41
  • I can't find these unbranded releases anywhere, seems it is in development and should of released with version 42 of Firefox but I just can't find a download link anywhere, so I guess it never did :( Just have to wait for 44 to come out. – Mark Kirby Dec 18 '15 at 9:50

I appears that Mozilla has finally made unbranded builds available at the following location:



There are two temporary solutions that may help you out for a short period of time. This can be all that is needed, for instance if a developer is already working on getting an add-on signed but has not succeeded yet.

Load about:config in the browser's address bar.
Confirm you will be careful if the prompt appears.
Search for xpinstall.signatures.required.
Double-click the preference to set it to false.

This overrides the add-on signing requirement in Firefox 43. Please note that Mozilla plans to remove the flag when Firefox 44 is released for Firefox Stable and Beta.

The above is taken from http://www.ghacks.net/2015/12/16/what-you-do-when-firefox-disables-installed-add-ons/

Re. the unbranded version, there's no clarity on when it will be available.

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