> First, you're assuming that users have favorite websites, and that those sites wouldn't work. Both are true almost in my case. Browsers based on older Firefo

> First, you're assuming that users have favorite websites, and that those sites wouldn't work. Both are true almost in my case. Browsers based on older Firefox versions such as Palemoon and Seamonkey don't work with GitLab and Github - which are not my "favorite" websites but rather, are hard to avoid. > I don't think many users would even notice if their browser stopped supporting things that browser developers consider edge cases that eat up dev time That's not the issue. The issue is that some websites use the shiny new features - probably through some new shiny framework - that older browsers don't support. And this is a loser's game for browsers done from scratch, because by the time they implement one missing features, two others have been standardized. That will probably kill Firefox too.