Yeah so my proposed fix is not really a fix but a way for you to keep working. By using the solution above, every physics object will be interactable through scenes, which defeats the purpose of MRS completely.
The way forward would be to make PhysicsRaycaster to use scene-specific physics.
Take a look at uGUI/PhysicsRaycaster.cs at 2019.1 · Unity-Technologies/uGUI (github.com)
You can subclass PhysicsRaycaster and handle physics per-scene basis.
We might consider providing a helper CoherencePhysicsRaycaster, but it’s not a priority right now. So IMO best chance you’ve got at getting this to work without giving up on uGUI is to create your custom PhysicsRaycaster.
CoherenceScene has a reference to the physics scene, and ticks it. Let us know if there’s anything we could do to improve this API to allow for your implementation to work!
