If you haven't solved the game, don't read any further.
So I'm trying to get the unbreakable bottle opener from the glassblower. I try to grab it a few times, I try a few things on it... and then Guybrush glitches, and plays the animation of him getting the glass blower, blowing the bottle and getting the map.
Meanwhile, the original bottle breaker is still sitting on the little stool thing.
I don't know how, but I think I triggered some kind of bug. I don't think I did anything which meant I should have gotten the bottle opener. First time I've found a bug in a TellTale game, so that's a pretty amazing track record :)