> I don't understand why anyone would bother forking Firefox when forking Chromium is available which is more advanced and more modular.

No uBlock is a deal breaker. Chromium is stuck with the neutered uBlock Lite thanks to Manifest V3.

> Brave browser fulfills that role

Sure, and it's also funded by VC money. How long until the vultures start swooping in to get a return on their investiment?