Personas Flavor - Conditional Logic Need to Wait for Pop-up

Greetings,

We're on SAP Personas v3.08.2

I have some conditional logic on the flavor for IW21 that depends on whether or not the equipment number lookup is successful. When the lookup fails, there is a pop-up window displaying the error. The problem is, the pop-up window takes a second or so to appear, so I'm not sure how my script can wait for this window. If the lookup fails, I want it to stop the execution of the script, otherwise, if the popup doesn't appear it should continue.

How would I go about this?

Thank you