First of all, this is not for 0.13.0. The version of the bug is 0.13.1.
OK, I was playing with my friend, and he said, "That's so weird. Your pickaxe is not moving but your hand is." Then I starting mining while looking at his screen, and he sees my hand moving but not my pick. Then I told HIM to mine and I took a picture. The picture isn't the best, since I need a VIDEO to capture it. The picture on the left shows the version. Just look in the bottom left corner. I took the picture because of the splash "hurnerjsger," which is the sound of a villager. And I like villagers.