@feld yeah, it's hard, people have no idea how much money it's need to keep a team of people working full time in such a thing. I always laugh when I read they say "I'll just use fork X" as if that's not just a reskin and some changes to some settings with no real developers working full time on a browser.
@vascorsd Ops people, security people, QA, i18n, the engine devs, the GUI devs, representation and participation in the standards bodies...
Probably going to need to drop support for some OSes and arches...
Linux and Postgres are pretty huge themselves but there's a business case for paying devs to work on it full time, so the most active contributors are fully funded.
Which company NEEDS Firefox and could fund it? None, really. Your business is not going to have a competitive edge by supporting Firefox...