I've definitely seen the chest one multiple times, with not having to unlock the door as I can just go through the other end! I also am pretty sure I had the glitch with the swamp too, I had it after floor 3 where instead of getting to the swamp the post-key stairs took me to the caves instead.
I was very confused and thought I had encountered a bug until I realized that oh no! The block being removed on self was fixed to actually work with the ninja armour! Noooo!