We have tested the functionality and below are our observations:-
Case1:By default focus is with Menu Item “File” when the MDI parent is loaded.. At this moment , if we close the panel by clicking on the ‘X’ button then first click will move the focus from Menu Item and keeps the focus on the paenl. Second click will close the window.
Case2:In case if the focus is with any child tab or on panel then with single click panel can be closed. Click on the panel to move the focus from Menu item and close the panel. With a single click panel gets closed.