1) Start SB
2) Open the attached file
    => the assertion below is reported (custom_control.fxml)


at com.oracle.javafx.scenebuilder.kit.fxom.FXOMCollection.<init>(FXOMCollection.java:61)
at com.oracle.javafx.scenebuilder.kit.fxom.TransientObject.makeFxomObject(TransientObject.java:152)
at com.oracle.javafx.scenebuilder.kit.fxom.FXOMLoader.endElement(FXOMLoader.java:262)
at javafx.fxml.FXMLLoader.processEndElement(FXMLLoader.java:2836)
at javafx.fxml.FXMLLoader.loadImpl(FXMLLoader.java:2526)
at javafx.fxml.FXMLLoader.load(FXMLLoader.java:2419)
at com.oracle.javafx.scenebuilder.kit.fxom.FXOMLoader.load(FXOMLoader.java:83)
at com.oracle.javafx.scenebuilder.kit.fxom.FXOMDocument.<init>(FXOMDocument.java:74)
at com.oracle.javafx.scenebuilder.kit.editor.EditorController.updateFxomDocument(EditorController.java:1731)
at com.oracle.javafx.scenebuilder.kit.editor.EditorController.setFxmlTextAndLocation(EditorController.java:583)
at com.oracle.javafx.scenebuilder.app.DocumentWindowController.loadFromFile(DocumentWindowController.java:347)
at com.oracle.javafx.scenebuilder.app.SceneBuilderApp.performOpenFiles(SceneBuilderApp.java:431)
at com.oracle.javafx.scenebuilder.app.SceneBuilderApp.performOpenFile(SceneBuilderApp.java:380)
at com.oracle.javafx.scenebuilder.app.SceneBuilderApp.performControlAction(SceneBuilderApp.java:135)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController$ApplicationControlActionController.perform(MenuBarController.java:1426)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController.handleOnActionMenu(MenuBarController.java:970)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController.access$800(MenuBarController.java:86)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController$15.handle(MenuBarController.java:963)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController$15.handle(MenuBarController.java:959)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
at javafx.event.Event.fireEvent(Event.java:204)
at javafx.scene.control.MenuItem.fire(MenuItem.java:462)
at com.sun.javafx.scene.control.GlobalMenuAdapter$5.handle(GlobalMenuAdapter.java:158)
at com.sun.javafx.scene.control.GlobalMenuAdapter$5.handle(GlobalMenuAdapter.java:156)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.event.Event.fireEvent(Event.java:204)
at javafx.scene.control.MenuItem.fire(MenuItem.java:462)
at com.sun.javafx.tk.quantum.GlassSystemMenu$6.action(GlassSystemMenu.java:234)