[SOLVED] How to disable this gesture?

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http://www.kubuntuforums.net – Hi! :-) At Shortcuts and Gestures (-> Custom Shortcuts) I've deselected (disabled) the Gestures option. Still when I move the mouse pointer at upper-left corner, it presents me the active windows to select one (an Alt-TAB alternative)? Probably it's a Plasma gesture, so disabling custom gestures didn't affect it. How can I disable it? I'm using the keyboard for that (Alt-TAB). TIA! :-) (HowTos)