I can see what's on my opponent's Crypt

[AdamH]

Once my opponent starts taking cards off their Crypt I shouldn't know what's there, but if I hover over their set-aside area I'm able to see some face-up cards. I'm not even sure if they're the right cards. In either case I should be seeing face-down cards on my opponent's Crypt like I do for stuff like Archive.

[Dwedit]

Just had to check, and indeed crypt wants cards face down.  It requires the treasures to be face up at time of being taken from play, and that proves that they are treasures.
Would Stash need its special card back revealed, or does it just stay underneath the card so it's not shown?