Using an older version of Firefox?

Apparently, ALL add-ons will stop working on Firefox versions older than 128 (or older than ESR 115.13+) on March 14th, in just a few days from now.

To keep using your add-ons including Privacy Badger, you will need to update Firefox: https://support.mozilla.org/en-US/kb/root-certificate-expiration

Update Firefox to prevent add-ons issues from root certificate expiration | Mozilla Support

Update to Firefox 128+ by March 14, 2025, to avoid issues with add-ons, DRM media and essential features due to an expiring root certificate.