Bug when killing app at scroll preview

[aqrig1]

Actual behaviour: If you scroll over open app and then close it by middle-click or "X" button, you will stay on this preview screen: background blurred and you have to click somewhere to get back to your open app.
The same when you open all apps by hot corner or shortcut and close all of them: you wont be reverted to desktop until click,
Expected behaviour: you will get back to previous app after closing or desktop, if you close all apps.