Adventure mode - Breaking long grass while holding both left and right click glitches out the hand

While playing adventure mode, hold both the left click and the right click button.

Then smash instantly smashable blocks such as grass.
Try it on a couple of blocks.

The arm animation will no longer display for instant smashable blocks.

When moving to a non-instant block, the arm will work again, but will return to its bugged state when you move your view to a instant smashable block.