[–] jobes [OP] 0 points (+0|-0)

The poster believes it's caused by "a bug where text typed into the chat is occasionally misinterpreted by the game [as] input for navigating the menu" and Blizzard seemingly concurs, as the issue has now been resolved.

However, after getting in touch with Blizzard and explaining what happened, the developer refused to refund the 300 legacy credits, insisting that "all those unlocks are meant to be final", adding "if you believe there was a problem with the game which caused this to happen, please be sure to provide feedback via our forums". And that was it.