java.lang.AssertionError
   at org.openide.text.CloneableEditor$DoInitialize.initNonVisual(CloneableEditor.java:568)
   at org.openide.text.CloneableEditor$DoInitialize.run(CloneableEditor.java:324)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1415)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1954)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.AssertionError
   at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:1453)
   at org.openide.text.CloneableEditor$DoInitialize.<init>(CloneableEditor.java:291)
   at org.openide.text.CloneableEditor.initialize(CloneableEditor.java:226)
   at org.openide.text.CloneableEditor.componentShowing(CloneableEditor.java:202)
   at org.openide.windows.WindowManager.componentShowing(WindowManager.java:332)
   at org.netbeans.core.windows.WindowManagerImpl.componentShowing(WindowManagerImpl.java:1022)
   at org.netbeans.core.windows.view.DefaultView.changeGUI(DefaultView.java:161)
   at org.netbeans.core.windows.ViewRequestor.dispatchRequest(ViewRequestor.java:269)
   at org.netbeans.core.windows.ViewRequestor.processRequest(ViewRequestor.java:245)
   at org.netbeans.core.windows.ViewRequestor.postRequest(ViewRequestor.java:183)
   at org.netbeans.core.windows.ViewRequestor.scheduleRequest(ViewRequestor.java:123)
   at org.netbeans.core.windows.Central.activateModeTopComponent(Central.java:1761)
   at org.netbeans.core.windows.WindowManagerImpl.topComponentRequestActive(WindowManagerImpl.java:1145)
   at org.openide.windows.TopComponent.requestActive(TopComponent.java:843)
   at org.openide.windows.CloneableOpenSupport$1.run(CloneableOpenSupport.java:99)
   at org.openide.util.Mutex.doEvent(Mutex.java:1338)
   at org.openide.util.Mutex.writeAccess(Mutex.java:452)
   at org.openide.windows.CloneableOpenSupport.open(CloneableOpenSupport.java:95)
   at org.openide.text.CloneableEditorSupport.open(CloneableEditorSupport.java:467)
   at org.openide.awt.ActionDefaultPerfomer.actionPerformed(ActionDefaultPerfomer.java:67)
   at org.openide.awt.ContextAction$Performer.actionPerformed(ContextAction.java:223)
   at org.openide.awt.ContextManager.actionPerformed(ContextManager.java:237)
   at org.openide.awt.ContextAction.actionPerformed(ContextAction.java:106)
   at org.openide.util.actions.ActionInvoker$1.run(ActionInvoker.java:90)
   at org.openide.util.actions.ActionInvoker.doPerformAction(ActionInvoker.java:113)
   at org.openide.util.actions.ActionInvoker.invokeAction(ActionInvoker.java:96)
   at org.openide.awt.GeneralAction$DelegateAction.actionPerformed(GeneralAction.java:216)
   at org.openide.explorer.view.TreeView$PopupSupport.mouseClicked(TreeView.java:1556)
   at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:270)
   at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:269)
   at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:269)
   at java.awt.AWTEventMulticaster.mouseClicked(AWTEventMulticaster.java:269)
   at java.awt.Component.processMouseEvent(Component.java:6109)
   at javax.swing.JComponent.processMouseEvent(JComponent.java:3276)
   at java.awt.Component.processEvent(Component.java:5871)
   at java.awt.Container.processEvent(Container.java:2105)
   at java.awt.Component.dispatchEventImpl(Component.java:4467)
   at java.awt.Container.dispatchEventImpl(Container.java:2163)
   at java.awt.Component.dispatchEvent(Component.java:4293)
   at java.awt.LightweightDispatcher.retargetMouseEvent(LightweightDispatcher.java:4461)
   at java.awt.LightweightDispatcher.processMouseEvent(LightweightDispatcher.java:4134)
   at java.awt.LightweightDispatcher.dispatchEvent(LightweightDispatcher.java:4055)
   at java.awt.Container.dispatchEventImpl(Container.java:2149)
   at java.awt.Window.dispatchEventImpl(Window.java:2478)
   at java.awt.Component.dispatchEvent(Component.java:4293)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:604)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:134)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:275)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:200)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:185)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:177)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:138)