Firefox is far from dead. I switched back to Firefox from Chrome and it’s been freeing. The extension migration was a pain, but I found almost everything I needed and purged stuff I didn’t.
i'm a firefox user, but firefox is 2,4% from being dead. that's still a lot of people but dangerously close to the kind of numbers where people stop bothering to test if their websites work in it (if they were even doing it to begin with, let's be honest)