Not sure if this is intended behavior ... it seems unusual to me. When I close the one and only resource I have open (doesn't matter which one) the "About Verbum" pop-up window is displayed at the top but in an unusual position. See screenshot below.
macOS Catalina 10.15.7
Verbum 9.0 SR-1 9.0.0.0172
Is it possible that you already had that floating window open?
Dave===
Windows 11 & Android 8
That must have been it. I closed everything down and tried again. No pop-up. Strange thing is that I didn't see a pop-up when I minimized the main window. Hmmm. Error on my part :)