Thank you for testing Firefox Beta! This version is exactly similar to the previous (mistakenly tagged) v81.0.0 Beta.
The only additional changes here are:
Updating to AC 54.0.1 to add some migration telemetry https://github.com/mozilla-mobile/android-components/pull/8090
Missing default browser setting #13827
Including below the changes added in v81.0.0
Easy session navigation #11452
Force-refresh tab #2681
Bug and crash fixes