When fooling around with the elytra item in Creative, I found that due to the way the hitbox changes, you can stand on one-block high spaces when you have stopped flying. You are (only just) not in the wall though, and trying to walk into it will push you out while flickering the suffocation screen.

What I expected to happen was that I would not be able to stand on the one-block high gap and I would fall to the ground below.

What actually happened was that I was, by around 0.01 blocks, standing on the platform that would normally be impossible to stand on.

Steps to Reproduce:
1. Create a wall with a one block high gap. It can be any width you like, it doesn't change the bug.
2. Equip the elytra item, and fly towards the gap from a distance. (It works better if you do slightly above and when doing this continue pressing against the wall.
3. If done correctly, you will find yourself strangely but properly standing on the one-block gap.

It should be noted this trick also works if thin blocks are in the gap (e.g. fences, glass panes). Screenshots will soon be supplied.