Firefox just disabled ALL my addons, including the current uBlock Origin 1.18.6. In my post about this I pointed out it only happened in FF 66.0.3 on my Windows 7 PC. The copy of FF 66.0.3 on my Windows 10 PC has the same group of addons, and they're not disabled there. Tis a conundrum.

Sorry, the Add-ons team is working on a fix for this. It looks like a certificate used to sign many popular extensions expired. (The verification process checks that certificate.)

I don't know how soon re-signed versions of those extensions will become available, or whether another workaround will be discovered. We are all hoping to learn more soon.

In addition to disabling uBlock, Avast Online Security has been disabled!

See also:

• Bug 1548973 - (armagadd-on-2.0) All extensions disabled due to expiration of intermediate signing cert

(please do not comment in bug reports
https://bugzilla.mozilla.org/page.cgi?id=etiquette.html)

Mozilla has rolled-out a fix for this. The fix will be automatically applied in the background within the next few hours, you don’t need to take active steps.

In order to be able to provide this fix on short notice, they are using the Studies system. You can check if you have studies enabled

1. Go to [=] > Options > Privacy & Security.
2. Make sure Allow Firefox to install and run studies is check marked.

I you had it disabled, you can disable studies again after your add-ons have been re-enabled.

They are working on a general fix that doesn't need to rely on this and will keep you updated.

See also:

• https://blog.mozilla.org/addons/2019/05/04/update-regarding-add-ons-in-firefox/