@Gargron I agree, but for me, it's not just on desktop. Firefox on mobile (Android, in my case) is the ONLY browser I can use on mobile.
Sync works great, sending tabs to other devices works perfectly, the built-in password manager autofills apps well (although it could be improved), and it has extension support. Extensions is crucial because I can install UBO and block ads.
Booting up Chrome on Android without an adblocking DNS is a disgusting experience. I HATE ads being shoved in my face.