Hi,
Stemming from #15647:

Is your feature request related to a problem? Please describe.

At the moment screen curtain relies on full screen magnification flag, which returns True if running on Windows 8 and later. Since NVDA requires Windows 8.1 now, there is no need for this flag but add-ons may use it for some time.

Describe the solution you'd like

Deprecate winVersion.isFullScreenMagnificationAvailable flag, and in screen curtain module, return "True" in check method.

Describe alternatives you've considered

Leave code as is.

Additional context

Thanks.