#include causes UI to immediately close?

I’ve been writing scripts for many years and I have created a large library of helper “include” scripts that I share between scripts, but they have never worked when I need a UI Window. Is this a known behavior?

I just went through a long trouble shooting session with AI and tested all kinds of configurations and here is what I know

the included files run and there are no errors - I can verify defined variables and functions when I run the script, but any UI fails to load

the UI shows if instead of #include, I eval() the file

the UI shows if I interrupt the script with an alert() window and the UI will remain visible till I dismiss the alert

I’ve tested it with stripped down scripts with no logic just the UI. stripped down include files, even empty ones, the conclusion is the same. #include causes windows to not show, or close immediately. i have “#target illustrator; #targetengine main” at top. etc.

Is this the expected behavior?