From FlightGear wiki
| This article describes content/features that may not yet be available in the latest stable version of FlightGear (2020.1).|
You may need to install some extra components, use the latest development (Git) version or even rebuild FlightGear from source, possibly from a custom topic branch using special build settings:
This feature is scheduled for FlightGear (unknown).
If you'd like to learn more about getting your own ideas into FlightGear, check out Implementing new features for FlightGear.