hermie When plugin teleports player to their bed, it basically gets the exact position of the bed (which is in the vertical and horizontal middle of it) and teleports player to that position. Because of that the position has to be shifted upwards, so the player won’t be teleported inside of his bed, he has to be teleported a bit above it.
That’s what the TeleportHeight does, it is an option, because some modded beds that are higher than vanilla beds need to have this parameter adjusted.