Hi James,
Check out Microflow Timer widget from the App Store. With this widget, you can set a timer of when do you want to execute a microflow.
In your case, you can select the microflow/nanoflow to execute, and set it to execute once only. That should do the trick.
we do this sort of a thing with javascript to close the modal popups:
$('.mx-underlay').click(function() { $('.modal-close').click(); });
you’d need to rewrite a bit, with onpageload and maybe a timer because mendix loads pages a bit delayed.