GitHub also blocks their built-in fork UI functionality when the original repo's owner uses the site's "block" feature against you, which doesn't align with my expectations. Ironically, anyone affected by this poorly implemented blocking behavior (and thereby copying the full repo instead of forking) would be protected from this bug by the OP.
According to the documentation I remember reading, blocking someone would delete their forks of your repos (including public ones) back then. I believe this is no longer the case.
