Wow, very interesting. Although I'm on GH every day, I seldom look at the base GH page and so I would not have noticed this for a long time. Many thanks for posting this. The article is very interesting.
One thing I hadn't known about before was Github Discussions (beta): https://github.com/home#home-community
Everything seems to work for me. Firefox latest stable release
I get terribly jittery rendering in chrome (despite being on a powerful desktop that is doing nothing else).