I'm working on Gtk application that uses OpenGL viewport inside Gtk through GtkGLArea (using Gtk 3.x). The application is working correctly on most of the machines (and both, Linux and Windows (8.1, 10) operating systems.
Now none of the machines I've tested this with has the problem, except one - Dell E5470 Latitude - with Windows 10. Whenever the application is maximized, no drop downs from menu appears, and application isn't even visible when F.e. sharing screen through WebEx. It is like Windows would have switched to different mode like 'game performance mode' (upon detecting OpenGL context) and doesn't allow dropdowns, etc. rendered at all.
When I restore window to unmaximized size - everything suddenly works properly (drop downs, etc.). This happens only on that one specific machine, other machines work properly.
I know this might not be strictly GTK-related, but more Windows-setup related - although it might be possible somebody reading the gtk-list might have idea what is going on.