This doesn't work since Yosemite!
PLEASE FIX IT IMMEDIATELY.
If I close the case, it may logout OR just have the dual screen mode (even I close the case, so I can't see the screen on my macbook, the apps still run on the invisible screen, mouse can go into that screen, which is VERY ANNOYING)
MacBook Pro (Retina, 13-inch, Late 2013), OS X Yosemite (10.10)