The good news is that development could easily be funded by donations. It's only a few million. Enough to keep a few dozen people employed.
The bad news is that donations are unlikely to happen with the current massive misspending on overpaid people with no technical background that don't code that spend 95% of their budget on themselves, support staff that also doesn't code, offices they don't need, commercial products that flop, monetization schemes that fail, etc.
I wouldn't. And I'm a user! Mozilla needs to be restructured. And ideally they diversify their commercial ecosystem as well. Because they are way too dependent on Google.
If you look at Rust, created by Mozilla, they are set up in a more sane way. There's a foundation. It's well funded with sponsorships from the big companies that use and depend on Rust. Those companies employ people that contribute to Rust. Many OSS organizations are set up like that. It works. The diversity of contributors and commercial sponsors ensures neutrality and longevity. No single company has veto power. As long as valuable tech comes out, companies stay involved. Some disappear, new ones come along. Linux development works like that as well.
Ironically, Chromium at this point is better positioned to become like that. The main issue is that Google still employs most of the developers and controls the roadmap. But there are quite a few commercial chromium based products: Edge, Brave, Opera, etc. that each have development teams using and contributing to it. Add Electron (has its own foundation, based on chromium) to the mix and the countless commercial applications using that and you have a healthy ecosystem that could survive Google completely disengaging if they'd be forced to split off their browser activities.
I use Firefox mainly because of the iron grip keeps over Chromium and it's clear intent to cripple ad blocking, grab user data, and exploit its user base. But I worry about the dysfunctional mess that is Mozilla.