An interesting bug

Question

An interesting bug ive come across, not sure if its been discovered before.

Create a new form,
Set the TransparencyKey of the form to anything.
Add 2 buttons
Button1 maximizes the window
Button2 restores the window (sets its windowstate to normal)

when you maximize then restore the window, you will notice that there is no smoothanimation to the restore position, and, if you have a control set up to move the window, you will notice that the graphics behind the window are not refreshed.

They are refreshed, however, if you minimize the window.

Workarounds anyone?