Remove the event listener for the touch event in Amazon Sumerian.

AnchorPositioning.js

// Cleanup. When this script stops, also remove the event listeners.
// This is especially important here, as Sumerian doesn't always reliably
// clean up all the runtime-registrations when you repeatedly start the scene.
ctx.onStop(
	() => {
		console.log("Removing touch event listener.");
		this.internalWorld.sumerianRunner.renderer.domElement.removeEventListener('touchend', performHitTestCallback);
		// For testing on the PC with a mouse
		//this.internalWorld.sumerianRunner.renderer.domElement.removeEventListener('mouseup', performHitTestCallback);
	}
);