HTML5 is a debatable chicken-and-egg; one could argue that the standard came first even though a few parts were implemented by browsers prior. And what about XM

HTML5 is a debatable chicken-and-egg; one could argue that the standard came first even though a few parts were implemented by browsers prior. And what about XML? SVG? Most of the examples you give are early innovations made by browsers because the standards committees were weak back then. I kind of feel like you need both (standard + code) for an effective solution on the web. One inevitably has to come before the other, but I don't think it's always code.