The major feature coming in X-Plane 11.20 is native support of virtual reality, or VR. You can now try out X-Plane VR by grabbing the latest beta!
The focus of this build is VR preview and testing on a wide variety of hardware configurations, so at this time the beta does not contain many changes for those without VR headsets.
Those interested in previewing X-Plane VR can check out full release notes here, or this article on how to get started with VR.
