1. A method of handling events generated by user interaction with a display that includes a first window and a second window, including: generating a popup control for the first window responsive to a first user event representing user interaction with the first window; in circumstances when the user relocates a cursor from the first window to the second window and a mousedown or touch start event, collectively referred to as the mousedown event, generated within the second window, is suppressed from propagation to the first window, receiving a mouseup or touch end event, collectively referred to as the mouseup event, propagated from the second window and a location of the mouseup event, responsive to the mouseup event in the second window, triggering a dismiss class within the first window, wherein the dismiss class dismisses at least a portion of the popup control of the first window.