I was trying to test my texture pack, but then this glitch started happening.

How to Reproduce glitch:

1.) Load world with a texture pack
2.) In the ingame menu, go to Options\Texture Packs
3.) Open texture packs folder and add/remove one of the textures from the texture pack in use
4.) Click on the texture pack in the list
5.) Go back to world

This glitch isn't that bad because it fixes it's self after a bit, but it's still a glitch.