FXAA Block and Skin bug

While playing around with the newest snapshot while on create, i placed the worst graphics i could get in Minecraft.
Then i went to check on the Super Secret Setting (which im not going to spoil here) and set to FXAA type.
Then, you can see at the screenshot what happened

How to:
1-Not entirely sure if this does anything but, to make sure, set the graphics to the worst avaiable
2-Goto a creative mode world
3-Use Super Secret Settings and set shader to FXAA
4-Open up Survival Inventory
5-It should be with an inverted sking with no side textures and chest bottom being over the top texture