@alcinnz@aleph@neauoire True, that said in the ones that come to mind: - RSS/Atom, which browsers sadly tend to ignore - WHATWG where I think W3C still pulls snapshots from - JavaScript, which has a *lot* of libraries out there, and one of the very rare languages with an official open-source testsuite ( https://github.com/tc39/test262 )
@aleph@neauoire Although not everything W3C is related to browsers (like JSON-LD, RDF, SPARQL, Epub, SocialWeb (ActivityPub, ActivityStreams), … are irrelevant).
Wouldn't be surprised if you could ignore more than half of W3C stuff for the scope of a browser.