247
Their ideas are as interesting as they are frightening
(ttrpg.network)
I once had a player that wanted a Decanter of Endless Water just to waterboard people 😳
You're right, and the rules (both 3.5 and 5) even explicitly state that after ten minutes the creature suffocates. I was hoping that the RAW was simply "holds enough air for a Medium creature to breathe for ten minutes" which I could try to argue was merely a statement about the inner volume of the bag.