looks like rendering adblockers extensions obsolete with manifest-v3 was not enough so now they try to implement DRM into the browser giving the ability to any website to refuse traffic to you if you don't run a complaint browser ( cough...firefox )
here is an article in hacker news since i'm sure they can explain this to you better than i.
and also some github docs
The sad part is Mozilla is more of a political organization than just the developers of Firefox now. So you're donating for their lobbying, not just browser development.
Firefox needs new ownership. But it's kinda hard considering how big of a project a browser is nowadays.
Not even a single dime can go towards FF development, as it is done by a Corporation (Mozilla Corp.) which can't legally take donations.