Mozilla is fixing a bug that stopped Firefox extensions from working

Last night, Firefox users noticed an issue with their browsers: they couldn’t install extensions, and their existing add-ons stopped working. Mozilla says that the issue is due to a certificate expiration, and that it’s working to fix the issue.
In a blog post, Mozilla says that it’s identified the issue, and it’s begun rolling out a fix for users. “The fix will be automatically applied in the background within the next few hours. No active steps need to be taken t