window size is very small and cannot be maximized

[kolydart]

On a windows 10 pc, when I open the application, the window is really small. So small, I cannot click on the buttons. Also, no maximize action has any result, like Drag Corners, Alt + Space, Windows Key + Arrow keys, Compatibility Mode in app properties, even sizing applications like Sizer.
This is a screenshot of the opened app:

[AlexKalopsia]

Same issue on Win11

[WachRod]

I've got same problems in windows 10.