The trap doors I place on the wall are facing down. When I reopen the world again the trap doors will change their position.

gatharian added:
Steps to duplicate:
-Make a wall at least 3 blocks high.
-Place 3 wooden trap doors on the top half of the block on the wall.
-Make the trap doors face the ground touching the wall. (See before photo.)
-Reopen your world.
The trap doors will change their position on the wall.

See photos attached.