Mixed reality only work in the first scene

When a mixed reality scene element OVRSceneAnchor is destroyed, it get ignored during the whole game session.
Opening Mixed reality a second time in another Unity scene is impossible, or very laborious.

This is because of recent changes in the Unity Integration SDK in OVRSceneAnchor.cs.
Problem is reproducible on v48 & v49. Not on v43.

I removed the line :
DestroyedSceneAnchors.Add(this.Uuid);
in OVRSceneAnchor.cs line 209 for a workaround. But maybe there is something I'm missing ?