Comment 2 for bug 129678

Ok, after further studding:

1) active auto_hide
( window preview aren't working )
2) go off the bar (the bar auto_hides)
3) let the bar come up
( window preview are working: place = on the bottom )
4) the bar is up
( window preview are working: place = on the bottom with bar_height between the bottom and the window preview = right place)
5) go to the bottom of the bar and to the left/right until your not longer on the and go up (the bar doesn't hide)
6) go back on the bar
(window preview is again not working)