Hi, PGBSoft !

Thanks for the control.

I found the bug (both IDE/compiled, win7): when there is no place to drop down the list it drow up, but under the control a translucent rectangle appears (see screenshot #1).
Furthermore, in such case, if you don't close the list, that rectangle left on the form forever (see screenshot #2).

https://prnt.sc/k9bn3q
https://prnt.sc/k9bn8s