when invoking Wrap In GridPane on the root node, one get :

Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
at com.oracle.javafx.scenebuilder.kit.editor.job.wrap.WrapInGridPaneJob.modifyChildrenJobs(WrapInGridPaneJob.java:87)
at com.oracle.javafx.scenebuilder.kit.editor.job.wrap.AbstractWrapInJob.buildSubJobs(AbstractWrapInJob.java:257)
at com.oracle.javafx.scenebuilder.kit.editor.job.wrap.AbstractWrapInJob.execute(AbstractWrapInJob.java:90)
at com.oracle.javafx.scenebuilder.kit.editor.JobManager.executeJob(JobManager.java:160)
at com.oracle.javafx.scenebuilder.kit.editor.JobManager.push(JobManager.java:66)
at com.oracle.javafx.scenebuilder.kit.editor.EditorController.performEditAction(EditorController.java:718)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController$EditActionController.perform(MenuBarController.java:989)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController.handleOnActionMenu(MenuBarController.java:714)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController.access$300(MenuBarController.java:79)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController$8.handle(MenuBarController.java:707)
at com.oracle.javafx.scenebuilder.app.menubar.MenuBarController$8.handle(MenuBarController.java:703)
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:203)
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:203)
at javafx.scene.control.MenuItem.fire(MenuItem.java:462)
at com.sun.javafx.tk.quantum.GlassSystemMenu$6.action(GlassSystemMenu.java:234)