GitHub won't load, "Unable to establish a secure connection." Where to dig?

Question

Computer networks

Some crazy thing happened.
Github stopped opening, Chrome writes ERR_CONNECTION_RESET. Safari says "unable to establish a secure connection".
And this is only through the home Internet, either from a computer or from a phone.
If you turn off Wi-Fi on the phone - everything works.
Of course, the rest of the Internet works as it should.
Where to dig?

Answer 1

habrahabr.ru/post/239021
You need to wait a bit, it should start loading normally soon.