Can't get the space bounds rectangle size (c++, native, focus3)

[voidroom]

Whenever I call xrGetReferenceSpaceBoundsRect to read space bounds rectangle size (for room-scale, XR_REFERENCE_SPACE_TYPE_STAGE), I get the same result: XR_SPACE_BOUNDS_UNAVAILABLE.

This happens on Focus3, OpenXR with native/C++ implementation (not using Unity or Unreal but I am curious anyone who uses them is able to get the size of that rectangular area. On anything else (at least so far) it works fine, ie. provides a proper result.

The origin point (placement and direction/forward) is coherent with the lobby's - forward is where I told it to be and 0,0,0 is roughly at the centre of whole area.

I suspect on of two (or I might be completely wrong which is also possible 😄😞

1. I miss something in AndroidManifest.xml file that tells explictly that the game is a room-scale experience. Or maybe during setup.
2. Either Vive Focus3 or OpenXR implementation for Vive Focus3 does not provide such rectangular area at all, ie. it is not possible to get any information about bounds while using OpenXR on Vive Focus 3.

I hardly believe that point 2 is the case. What am I missing then?