Jellyfin is not even in the ballpark of what Firefox is. A web browser is a giant OS at this point.
Blame the ones who need to be blamed - “leftist” women CEO capitalists who took over Mozilla once Brendan Eich stepped down. They ate Mozilla from the inside out. Their overwhelming focus on politics over software has helped cause this. And it shows, because they have been focusing on things like deplatforming, AI, Pocket, for years now. Bikini photo ops as malicious heads of Mozilla are cool for women I guess.
The truth is, the combination of relying on political wings (left or right) for development and opting to use Chrome based browsers has caused this. Donations would have been sucked away by those CEO leeches.