This is a fantastic idea and I'm really glad to see experimentation in this area. It's already great to look at how things like Webkit's dev tools are implement

This is a fantastic idea and I'm really glad to see experimentation in this area. It's already great to look at how things like Webkit's dev tools are implemented in HTML and see how that idea might be extended. At it's core, a browser is an HTML/JS rendering engine with some chrome to allow users to manage what pages they're looking at – and in most cases, that chrome is actually pretty minimal. It seems like a natural evolution to play with the idea of implementing that chrome in the natural UI language of the browser engine too. Yeah, the tools aren't there yet – but experiments like this will give us some scope to play around with what might be possible and identify the pain points that must be overcome to make it a reality. Great stuff.