Why does github.com slow down in Safari?

Question

safari

In the Safari browser on MacOS Sierra (and also noticed on the previous OS), the github.com site slows down a lot, other sites open normally, what could be the problem and how to solve it?

Answer 1

The case is in Roskomnadzor. Apparently, in a fit of tenderness, they blocked ocsp.digicert.com, which Safari (and many others) climbs to check revoked certificates.
I temporarily solved it by writing another address in /etc/hosts
72.21.91.29 ocsp.digicert.com
An article that helped solve the issue here:
www.shortcut.ru/2016/10/03/when-in-doubt-use-sniffer

Answer 2

It doesn’t slow me down at all, so it’s not about safari. True, I have El Capitan