When loading a new world in the latest snapshot, the first time you open your inventory (in survival mode) your character's skin will be displayed very oddly. (This does not happen in creative mode, but when I switched to survival from creative on a second world it happened again.) The bug went away after a few minutes - not sure what exactly caused it to fix itself.
Environment
Windows 10 64bit - Java 1.8.0_51 64bit
Duplicate of MC-83004 – If you have not, please use the search function in the future, to see if your bug has already been submitted.