@Corvus Any update on this? I recently got in contact with a Unity QA engineer, and they said that, on their end, they support OpenXR, which can interface with SteamVR and HTC HMDs; so I tried using it and found that, even though I set XRSettings.useOcclusionMesh to "false", and check that the "occlusion mesh" view in Unity Editor's game view is correct, there still seems to be another occlusion mesh, and it seems like it's constant for any game (i.e. that occlusion mesh stays on and is the same no matter what game or program I open). In other words, it seems like an overlay created by either the headset or SteamVR, so if there's nothing on your end that can be done about this, then that leaves only the people at Valve that could possibly help