Also happening to me. Restarting the Mac didn't help, restarting the iPad did help.

That's great to hear. Can anybody reply to see if I receive anything?

I've noticed this as well and filed a bug report to Apple exactly 6 months ago, still without answer. It is easily reproducible with this code:         let url = Bundle.main.url(forResource: "art.scnassets/texture.png", withExtension: nil)!         plane1.firstMaterial!.diffuse.contents = url.path         let node1 = SCNNode(geometry: plane1)         node1.position.x = -5         scene.rootNode.addChildNode(node1)         let plane2 = SCNPlane(width: 10, height: 10)         plane2.firstMaterial!.diffuse.contents = SKTexture(image: NSImage(byReferencing: url))         let node2 = SCNNode(geometry: plane2)         node2.position.x = 5         scene.rootNode.addChildNode(node2)