Game #5059 on frankfurt-test2
In turn 13 or 14 for Burning Skull, he played Black Market which discarded those cards automatically due to his having debt. To confirm that he hadn't messed up, he did an undo and played the Black Market to the same result. This all went smoothly.
On my following turn, I started out the turn being able to see the cards that his Black Market had revealed, as one can see in the attached screenshot. Later that turn, when playing Black Markets of my own, this display went away and I was unable to see the cards I had the option of buying - an undo to before playing those Black Markets allowed me to see the cards.