Returns the number of the frontmost window that would be hit by a mouse-down at the specified screen location.
- macOS 10.6+
The location of the mouse-down in screen coordinates.
If non-0, the search will start below
windowwindow in z-order.
The window number of the window under the point. The window number returned may correspond to a window in another application.
Because this method uses the same rules as mouse-down hit-testing, windows with transparency at the given point, and windows that ignore mouse events, will not be returned.