What you call the "GSX window", is NOT a GSX window. It's the standard Simconnect menu window, which is shared between ALL 3rd party addons that use the standard way of creating a menu, which is by using the Simconnect interface.
GSX or any other 3rd party application that use that windows, doesn't have ANY control over its size or placement, it's done automatically by sim, without any control possible on our side, and sometimes the sim resizes it automatically for some reason, usually when selecting 3rd party airplanes.
Again, there's nothing we can do about it, the only possible operations you can do on that windows are resizing/moving with the mouse, and dock/undock it.
