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src/loaders/ObjectLoader.js

@@ -344,6 +344,8 @@ Object.assign( ObjectLoader.prototype, {
 					case 'TubeGeometry':
 					case 'TubeBufferGeometry':
 
+						// This only works for built-in curves (e.g. CatmullRomCurve3).
+						// User defined curves or instances of CurvePath will not be deserialized.
 						geometry = new Geometries[ data.type ](
 							new Curves[ data.path.type ]().fromJSON( data.path ),
 							data.tubularSegments,