I added pure-css comment folding here at lobsters 6 years ago.
I didn’t have an account at the time and the folding used js, which was not enabled for non-logged users. So I went looking into the code even though I didn’t now any ruby and submitted the small patch.
Bob also gave a talk about this (from his pub!):
Nice article. You should consider adding an RSS feed to the blog, so it’s easier to follow it.
Thanks! That’s in my todo list and I seem to have plenty of time these days.