Late on Friday May 3rd, we became aware of an issue with Firefox that prevented existing and new add-ons from running or being installed.
We are very sorry for the inconvenience caused to people who use Firefox.
Our team has identified and rolled-out a fix for all Firefox Desktop users on Release, Beta and Nightly.
The fix will be automatically applied in the background within the next few hours.
No active steps need to be taken to make add-ons work again.
Please note: The fix does not apply to Firefox ESR or Firefox for Android.
We’re working on releasing a fix for both, and will provide updates here and on social media.
To provide this fix on short notice, we are using the Studies system.
This system is enabled by default, and no action is needed unless Studies have been disabled.
Firefox users can check if they have Studies enabled by going to:
- Firefox Options/Preferences -> Privacy & Security -> Allow Firefox to install and run studies (scroll down to find the setting)
Source:
Update Regarding Add-ons in Firefox