[bgee]

Disclaimer: mainland Chinese here.

> most major domains outside of China are blocked

I don't think this is true; GFW works in a disallow-list fashion and domains have to be explicitly blocked (which is why people do keyword attacks[0]).

[0]: https://github.com/cirosantilli/china-dictatorship

[cirosantilli]

Certainly the block is manually controlled.

But I believe that GitHub is not blocked yet just because it is not "major" enough because it is used almost exclusively only by programmers.

If non-programmers started to use it more, I believe it will get banned.

[pta2002]

GitHub's been banned in the past. It made development work near impossible, so they unbanned it.