Except where noted, everything here applies to both Firefox 133 and the Firefox 128.5 ESR.

Policies

• The MicrosoftEntraSSO policy is now fully supported on both Firefox 133 and Firefox ESR 128.5.
• The Preferences policy has been updated to allow setting the preference security.pki.certificate_transparency.mode. This change only impacts Firefox 133 because the feature is not in the ESR.
• The Preferences policy has been updated to allow setting preferences that begin with identity.fxaccounts.toolbar.. This change is not in the ESR (yet).

Special Notes

Firefox 115 ESR is officially out of support for enterprises. Firefox 115 ESR users will be upgraded to the Firefox 128 ESR unless they are on Windows 7/8 or macOS 10.12/10.13/10.14.

We are extending Firefox 115 ESR support for Windows 7/8 and macOS 10.12/10.13/10.14 users until March 2025.

If you need to prevent upgrades for any reason, you can use the AppUpdatePin policy.