It's impressive how well the minimap works for bigger articles, I clicked around randomly and ended up at https://www.stefanjudis.com/notes/should-responsive-images-w... and the minimap feels slightly magical since it appears instantly and updates synchronously if I do things like select text.
It feels kind of disappointing that I can't interact with it to scroll around like in i.e. Sublime Text, but I imagine that's a little harder to do as the author of a website. It's still very cool to me that you can do something like this on the web, and I wonder how much work it would be to support this complex CSS feature in Chrome or Safari.