It's crazy how history repeats itself ... This reminds me of Mozilla Composer (http://en.wikipedia.org/wiki/Mozilla_Composer) back when the Mozilla Suite was still a thing and Firefox was in its infancy!
Not really comparable. Composer was a WYSIWYG editor for web pages; the WebIDE is an editor, but more importantly it manages the packaging and creation of manifest files of apps for you. I started with Composer and the output was so awful that I learned HTML instead. This doesn't hide any code from you or generates things you don't want. The templates of the apps are maintained by the community on GitHub.