On 14 March a root certificate (the resource used to prove an add-on was approved by Mozilla) will expire, meaning Firefox users on versions older than 128 (or ESR 115) will not be able to use their add-ons. We want developers to be aware of this in case some of your users are on older versions of Firefox that may be impacted.

https://blog.mozilla.org/addons/2025/03/10/root-certificate-...

This link has more useful information - but the short answer is to update Firefox or switch to the latest ESR 115 if you're on an OS that isn't supported by the latest versions.

https://support.mozilla.org/en-US/kb/root-certificate-expira...

> We want developers to be aware of this in case some of your users are on older versions of Firefox that may be impacted.

And yet the error doesn't say anything even remotely close to that, blaming the add-on instead.

I found this thread when my add-ons suddenly stopped working without warning and without explanation. The help page didn't mention it either.

Agreed. Frankly stinks of a dark pattern.

thanks!

Also had this issue in LibreWolf on macOS. Updating the browser fixed things for me.

  brew install --force --cask librewolf

thanks!