1. User clicks the scrollbar of a listbox in a formspec menu, focusing it. 2. User presses mouse button outside formspec menu. This doesn't cause a change of focus because the menu disallows it 3. The mouse event is delivered to the focused element (the scrollbar) 4. Since the mouse cursor is outside the scrollbar, the scrollbar passes the event to its parent (the listbox) 5. The listbox interprets this as a command to start selecting 6. User releases mouse button (still outside the formspec). This event is handled by the scrollbar and the listbox never sees it. 7. User moves mouse cursor over the listbox. Since the listbox is still in selection mode, merely moving the mouse selects items, without having to press a button.