See also https://forum.endeavouros.com/t/floorp-going-closed-source/52783
Edit: They claim they will make that part open source too, eventually, and it is due to behavior of another browser: https://github.com/Floorp-Projects/Floorp-core/issues/62
Edit 2: They just open sourced the private repository 7 minutes ago, 2024-03-24T12:39Z
Try Mercery for a boost in performance of about 8-20% dependent on machine: https://thorium.rocks/mercury
Or for better security/privacy try LibreWolf: https://librewolf.net
Normal Firefox has telemetry and poor default settings but is still feature rich if you take the time to config.
My small concern with Librewolf is getting security updates quickly. Cool project though. As I understand, the team has been better about quickly patching security vulnerabilities in recently months too.