Comment by berkes

> something that looks like HTML

This is surprisingly easy. Because the "this is HTML" is both vague and limited. HTML5 is remarkably vague and permissive.

Also, HTML has nothing to do with CSS nor with JS, nor with any DOM apis and not even with how stuff has to be rendered or if it has to be rendered at all.

There are numerous libraries and projects that can parse the WHATWG version of HTML. I'm not saying these are trivial or simple. But far simpler than a full rendering engine will ever be.