Intercept popup/window close

Is there a way to intercept/block a popup close that is triggered when a user presses the “X” on the top right corner of the popup? What I’m trying to do is give the user an indication that there are unsaved changes before fully closing the popup.
This would be in a Vision 8.1 project.

Welcome to the forums @mmcmahon !

I haven’t tried this, but can you alter the popup parent window’s closable property to make the “X” not visible at all until changes are saved?