SuperCard has a zoomWindow message that is sent when the Zoom Box is clicked, allowing the developer to intercept the event and define their own behavior.
Is there a like mechanism in LiveCode?
Zoom Box Message
Moderators: FourthWorld, heatherlaine, Klaus, kevinmiller, robinmiller
Re: Zoom Box Message
Nope, there is just the resizeStack message, but that is sent after the stack has been resized.. You would need to build an external to copy that functionality from SuperCard..