I've been a Firefox user for at least 15 years as well, and the recent UI updates in v89 is the first instance of me refusing to update Firefox.

I updated my user prefs file to permanently disable updates, so I'm remaining on pre-ProtonUI v88. Of course, I don't know how much longer I could sustain that because I'd also not receive security patches, but in the short term it's what I'm doing.

The new Firefox UI is incredibly frustrating, and feels like it walks back sensible UI principles. Removing icons in the main menu was celebrated as "de-cluttering" [0], when in reality icons improve ease of use. The "floating" tabs feel more distracting [1], when they claim the opposite. Heck, even user prompts no longer colorize the "primary action" button [2].

Also, what's with modern UIs becoming increasingly childish and watered down? The word I'd use to describe the new proton UI is "blurry".

[0] https://www.mozilla.org/media/img/firefox/releasenotes/note-... [1] https://www.mozilla.org/media/img/firefox/releasenotes/note-... [2] https://www.mozilla.org/media/img/firefox/releasenotes/note-...