This site is using Orgish, a custom variant of Org Mode.
It Is Still A Work In Progress
Orgish actually still sucks at parsing because Org Mode's syntax is pretty weird and giant and ambigious and using combine to build the parser was a bad idea.
You can disable line wrapping for a bit by wrapping your content in nbsp& hello world this won't be line wrapped! so cool! some more words! blah blah blah blah