Need help with random crash

I am working on a listbox subclass in a project where that besides a window, there is only that subclass.

I am getting a random crash on clean quit of the program running in the IDE. I have set autoquit to true, and the issue presents when I close the only window.

Would appreciate some guidance as to what may be triggering that issue. Here is the crash log :

CrashListBoxRecord.txt

TIA

Are you calling Quit in the CancelClose event?

No. Actually, I did not implement any event handler in the window. And in App, only Open to set Autoquit to True.