java.lang.AssertionError
   at org.openide.text.CloneableEditor$DoInitialize.initNonVisual(CloneableEditor.java:628)
   at org.openide.text.CloneableEditor$DoInitialize.run(CloneableEditor.java:367)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1452)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2032)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.AssertionError
   at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:1493)
   at org.openide.text.CloneableEditor$DoInitialize.<init>(CloneableEditor.java:332)
   at org.openide.text.CloneableEditor.initialize(CloneableEditor.java:248)
   at org.openide.text.CloneableEditor.componentShowing(CloneableEditor.java:223)
   at org.netbeans.core.spi.multiview.text.MultiViewCloneableEditor.componentShowing(MultiViewCloneableEditor.java:143)
   at org.netbeans.core.spi.multiview.text.MultiViewEditorElement.componentShowing(MultiViewEditorElement.java:134)
   at org.netbeans.core.multiview.MultiViewPeer.peerComponentShowing(MultiViewPeer.java:277)
   at org.netbeans.core.multiview.MultiViewCloneableTopComponent.componentShowing(MultiViewCloneableTopComponent.java:129)
   at org.openide.windows.WindowManager.componentShowing(WindowManager.java:339)
   at org.netbeans.core.windows.WindowManagerImpl.componentShowing(WindowManagerImpl.java:1163)
   at org.netbeans.core.windows.view.DefaultView.changeGUI(DefaultView.java:168)
   at org.netbeans.core.windows.ViewRequestor.dispatchRequest(ViewRequestor.java:273)
   at org.netbeans.core.windows.ViewRequestor.processRequest(ViewRequestor.java:249)
   at org.netbeans.core.windows.ViewRequestor.postRequest(ViewRequestor.java:187)
   at org.netbeans.core.windows.ViewRequestor.scheduleRequest(ViewRequestor.java:127)
   at org.netbeans.core.windows.Central.removeModeTopComponent(Central.java:1004)
   at org.netbeans.core.windows.ModeImpl.removeTopComponent(ModeImpl.java:478)
   at org.netbeans.core.windows.ModeImpl.close(ModeImpl.java:286)
   at org.netbeans.core.windows.WindowManagerImpl.topComponentClose(WindowManagerImpl.java:1284)
   at org.openide.windows.TopComponent.close(TopComponent.java:561)
   at org.openide.windows.TopComponent.close(TopComponent.java:548)
   at org.netbeans.modules.project.ui.ProjectUtilities$1.doClose(ProjectUtilities.java:204)
   at org.netbeans.modules.project.ui.ProjectUtilities$1.access$200(ProjectUtilities.java:103)
   at org.netbeans.modules.project.ui.ProjectUtilities$1$1.run(ProjectUtilities.java:139)
   at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:199)
   at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:682)
   at java.awt.EventQueue.access$000(EventQueue.java:85)
   at java.awt.EventQueue$1.run(EventQueue.java:643)
   at java.awt.EventQueue$1.run(EventQueue.java:641)
   at java.security.AccessController.doPrivileged(AccessController.java:0)
   at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:652)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:158)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:296)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:211)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:201)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:196)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:188)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)