When rotating your skin in the home-screen by clicking on it with your left mouse button, then holding it and moving your mouse left or right, it snaps back in to place when its almost at the end of the rotation. Its looks like it can't complete a full rotation, only about 340°, and in stead just snaps back.

See the video in the attachments

Steps to reproduce:

1. Open the home-screen of Minecraft
2. click on the skin in the lower right corner with your left mouse button and hold it down
3. while holding the left mouse button move your mouse right slowly
4. when the skin is almost at its original position, it will snap back to its original position

Observation:

When the skin is almost at its original position and you rotate it further, it will snap back to its original position.

Expected result:

The skin rotates smoothly and can rotate a full 360°.