This could be coupled with a search engine that indexes the pages which such a browser has been tested to display correctly. So you start off with a small inde

This could be coupled with a search engine that indexes the pages which such a browser has been tested to display correctly. So you start off with a small index that includes Richard Stallman's web site and a few thousand others, then add many more as things like flexbox or whatever get added. That feeds in nicely to the development process. The implementation of each new feature has the potential to open up thousands more sites to the index. In fact you could list bounties not in dollars but in the number of new sites a given feature can bring to the index. That way users look at the search engine to first discover the sites that work in the browser. You could go retro like the hand-crafted directory Yahoo used to use, or automate the process. Either way, it's a big improvement in UX. Compare: "While the supported sites do load fast and look great, their search doesn't cover enough sites for my browsing needs." To: "Wouldn't even load Reddit this thing looks hopelessly broken." I bet that it wouldn't take too much effort to get such a project to a place where you get a sizable index with the core feature being the lack of inclusion of sites with dark patterns. Like, an hour spent in this browser is filled with 80% critical reading whereas you'd just be infinitely scrolling through memes 80% of the time in Chrome...