Alt-tab flicker

[meh_register]

Hello,

Here's a bug:

When I have only one window opened and I try to alt-tab (even tough there are no windows to cycle) the skins flicker over the window.

When I have more than one window opened this doesn't happen.

I have Windows 7 with the classic theme.
I tried all the possible settings for the skins but it doesn't change anything, the same flicker still happens.