[SkyMarshal]

As long as web standards keep evolving you can never stop iterating on browsers. And with Google Chrome pushing some of those web standards additions, Firefox has to keep up or die.

Also, it is possible to continue iteratively improving a complex piece of software like a browser, beyond just the web standards race. Security, privacy, performance, and reliability/bugs/code correctness are areas where new computer science is constantly coming down the pipe and worth integrating. And maybe other things like AI or features for AR/VR systems, though it's more debatable whether those belong in general purpose browsers.

Browsers aren't Unix utilities that should do one thing and just one thing and thus can theoretically reach a state of "done". But even there it's not always a certainty. For example, "sudo" being superseded by a simpler more secure "doas", and then more recently by SystemD "run0". Even simple utilities continue to evolve.

[kjkjadksj]

Firefox is doing a lot more than merely keeping up with web standards. Learning to abrogate a web standard is not an impossibility. They are standards for a reason: to show other engineers how to interface with them. I'd consider a browser finished if it has tabs, bookmarks, history, and print. Same as we had 25 years ago.