Not sure if this has been brought up before, but for oculus users there are functionality built in to display desktop apps, just grab the window from deskjop view with the hand controller. I was not aware of this myself and fiddled around with steamvr and performance loss. This however worked like a charm - tried it with Navigraph and Littlenavmap:
Oculus: Place Charts-, Flightplanner-, GPS-Windows and others seamlessly into your VR-Cockpit - VR in X-Plane 11 - X-Plane.Org Forum
https://forums.x-plane.org/index.php?/forums/topic/138494-oculus-place-charts-flightplanner-gps-windows-and-others-seamlessly-into-your-vr-cockpit/