Playing these days with MR on DCS, using Meta Quest 3 + Virtual Desktop + Openkneeboard on the DCS OpenBeta (OpenXR). Seems promising (very early stages of testing):
Note that Openkneeboard was test to auto switch on/off depending on the area I looked at, it explains why the MR grid goes on and off.
Main limitation at this point is that you can only open a single-plane chroma compositing window for passthrough video, while (in this case) Hornet's cockpit displays are at multiple focal planes, which results is paralaxing on the VR zones I left for MDF/UFC retention.