I'm fairly sure that this bug has been reported already but I couldn't find it
When you press f5 twice to look behind you, a large part of the world won't load for a few seconds or until you move.

What I expected to happen was see the world

What actually happened was the world did not load for a few seconds

Steps to Reproduce:
1. open a world
2. press f5 twice to look behind you while not moving or moving the mouse
3. only about 1 chunk is loaded behind you for a few seconds or until you move your mouse