https://zen-browser.app/

Not being able to suggest an alternative for Chrome doesn't imply that Firefox is a good alternative.

On GrapheneOS they recommend Vanadium - a more secure Chromium fork - and specifically recommend against Firefox, but that's on mobile.

https://ladybird.org/

Helium has all the benefits of Chromium but none of the Google bloat or other crazy AI, Crypto, Gaming or whatever ideas other browsers ship.

Just uBlock Origin pre-installed

https://helium.computer/

FWIW I've recently moved from Firefox to Helium after 10+ years.

Yes, I hate that it's also Chromium, but no, there aren't real alternatives.