GUI - default button animation issue when using texture mode and pointer up does not occur over button

Hi, I notice that when using texture mode and a button, the default scaling animation is not reversed if the mouse is not released over the button:

http://www.babylonjs-playground.com/#ZI9AK7#7

Try clicking down on the button and moving the cursor before releasing.

In my own project it behaves a bit differently, I actually have to release it over something over than the canvas to reproduce.

Thanks for the great library in general and BABYLON.GUI in particular lately