alt Hacker NewsIdk man, but an engineer would've taken that and said something like: "Damn, yeah, good point, I shall add a sentence mentioning 5.3"
Because an engineer feels secure in their knowledge so that such an oversight doesn't make them suddenly defend their identity - it's just an oversight after all. Happens.
5.3 isn't available as open weights yet, and only became available via API three days ago. Prior to that the only way to access it was via a Z.ai subscription.