I use Fennec F-Droid with uBlock Origin, Privacy Badger, Decentraleyes, and HTTPS Everywhere.

Though sometimes I’ve contemplated switching to the Guardian Project’s Firefox Klar

I primarily use Firefox

Iceraven for browsing, Ironfox for anything that screams “don’t open this”, Fennec for stored logins only and Cromite if I ever needed a Chromium browser.

Vanadium for web apps, Cromite with auto delete for random websites, and IronFox with various plugins for web searches

Ironfox & Vanadium as main search, and Tor as the default, for opening links.

Define “best”?

Firefox and DuckDuckGo.

I’ve liked to use Fennec for few months now.

Best is subjective and recommendations would depend on your use case. Iceraven is my primary.

Firefox for Android doesn’t use chrome and has extensions including adblockers

On Android, I use Firefox. If Falkon were available on Android, I’d use that as well. I use both of those on Linux and BSD.

DuckDuckGo, i like the “burn everything” animation (and functionality, but mostly the animation)

Ironfox is ok. Though it’s not fully open source (the ui isn’t) I use Vivaldi

Vanadium on phone and hardened Firefox on laptop.

Waterfox. For really powerless machines dillo or “links2 -g.”

For android I just use firefox.