The player is capable of placing a bed in the same block they are standing in, causing them to automatically be forced onto the top of the bed.  Then, if the room is only 2 blocks tall, this will result in suffocation in the block above, and potential death.  There's no reason why it should be possible to place a bed in the block the player is standing in - you cannot do this with slabs, and beds are taller than slabs.  Tested on windows and iOS but is likely present on all platforms.