https://support.mozilla.org/en-US/kb/root-certificate-expiration
Why is this update important?
On March 14, 2025, a root certificate used to verify signed content and add-ons for various Mozilla projects, including Firefox, will expire. Without updating to Firefox version 128 or higher (or ESR 115.13+ for ESR users, including Windows 7/8/8.1 and macOS 10.12–10.14 users), this expiration may cause significant issues with add-ons, content signing and DRM-protected media playback.
If you don’t update, Firefox features that rely on remote updates will stop working, and your installed add-ons will be disabled. DRM-protected content, such as streaming services, may also stop playing due to failed updates. Additionally, systems dependent on content verification could stop functioning properly…
