The markdown in there looks like some horrible HTML / markdown hybrid. Yeah collapsing elements are cool if you’re viewing in a web browser but the point of markdown is that it’s supposed to look good in a plain text editor / terminal as it does when rendered and the raw version of that markdown file definitely isn’t.

Ultimately though I’m not going to complain that an open source developer has documented their free code in a way that differs from my own personal preferences. But before jumping on the bandwagon it’s worth thinking about whether you want your README to be readable as plain text as well.