It also doesn't solve any of the real problems with electron, since it doesn't actually give you any native software of any kind. Electron apps are annoying because they're wasteful, but also because they don't use my native UI elements. They don't conform with my expectations. And this doesn't solve that either.
So what DOES this do? For whom is it?
This is currently insanely difficult with Firefox. You need a custom profile for every website, with matching userChrome.css.