Brave is a good option too. I use brave for websites that are too junk to work in firefox. I have never used arc. I was coming from librewolf/floorp with sidebery. I really like the layout in zen, it hasnt shown the performance issues i sometimes saw in stock firefox and the vertical tab bar is good enough yo replace sidebery for me. Tge only annoyance ia how it sometomes weirdly display extensions in the truncated interface. Otger than that i am pretty happy.