note that each of these has their own issues. From a security/privacy pov, Mull, Mullvad Browser, and Tor Browser are generally most respected. I'm not familiar with floorp or pulse.
LibreWolf is one of the better Firefox forks but it doesn't have automatic updates and you're relying on a relatively small team to keep it up-to-date.
At that point, Mullvad Browser would be a better choice.
That's not accurate. LibreWolf has an automatic updater for Windows.[1] On Linux, updates for most applications are handled by the operating system's package manager, and LibreWolf also maintains a Flatpak.[2] On macOS, LibreWolf has a Homebrew cask.[3] Flatpak and Homebrew can be configured for automatic updates.
I've been very satisifed with LibreWolf and haven't experienced any significant issues.
> Mullvad Browser would be a better choice
Mullvad Browser is a nice fork, but it doesn't include any syncing (like Firefox Sync), which makes it a non-starter as a primary browser for anyone who uses that feature.