Firefox is unusable on Linux. Way too slow. But Brave browser is very snappy. It's the fastest chrome fork, and has great features, like vertical tabs, which have become essential to me.
Regardless which is my main browser, I have to keep both around, because they have different bugs, so there are rare cases with some sites that work well only with one of them.
A few months ago something happened with Chrome, which abruptly (after a version upgrade) has begun to start only after a very long and annoying delay. Perhaps it attempts to connect to some Internet address blocked by the firewall and it gives up only after a timeout.
In any case, this sudden slowdown of Chrome made me switch back to Firefox as my main browser, which is OK now, because Firefox on Linux has become fast again and it no longer has any noticeable speed difference vs. Chrome. Also some problems that Firefox had when playing YouTube videos have been solved.