Zelda? Not a Microsoft franchise, as I’m sure you know. Not that that stops the official Xbox Facebook account from telling you all about it…and also James Franco. For some reason!
This sort of thing isn’t quite an isolated incident—before, the Xbox UK account has posted about The Last of Us. That’s also not a Microsoft franchise, as I’m sure you’re aware.
EDIT: then there was this, as pointed out by reader waffle ryebread.
https://lastchance.cc/microsoft-accidentally-advertises-playstation-game-511558034%3C/a%3E%3C/p%3E