I tried to enable scene.createDefaultVRExperience({useMultiview: true}); but the quest then just shows black screen. Without this option the scene loads correctly. I remember that this worked some months ago. Could it be that some browser API changes has broken this one?
the next beta version will soon be released and will include the fix. until then you can build babylon yourself (or use the latest nighly) and npm-link it to your project, but it is sometimes too much of a hassle