I guess I played a card too fast, and...

cyclonus11

...got stuck with only four cards in the tavern for the rest of the match.

I must've played something before the card from the tavern resolved and I broke it, lol

dmnqwk

It's a funny bug and usually does involve too fast, because the missing card is located on top of your play pile.

If you picked a destroy card and targetted your play pile, you'd destroy it from there and the replacement would be in the correct position.