java.lang.IllegalStateException: Too many org.netbeans.modules.xml.schema.SchemaEditorSupport$4 (3) in shared RequestProcessor; create your own
   at org.openide.util.RequestProcessor.post(RequestProcessor.java:368)
   at org.netbeans.modules.xml.schema.SchemaEditorSupport.syncModel(SchemaEditorSupport.java:607)
   at org.netbeans.modules.xml.schema.multiview.SchemaSourceMultiViewElement.componentHidden(SchemaSourceMultiViewElement.java:325)
   at org.netbeans.core.multiview.MultiViewPeer.hideElement(MultiViewPeer.java:259)
   at org.netbeans.core.multiview.MultiViewPeer$SelectionListener.selectionChanged(MultiViewPeer.java:675)
   at org.netbeans.core.multiview.MultiViewModel.fireSelectionChanged(MultiViewModel.java:243)
   at org.netbeans.core.multiview.MultiViewModel.setActiveDescription(MultiViewModel.java:115)
   at org.netbeans.core.multiview.MultiViewModel$BtnGroup.setSelected(MultiViewModel.java:293)
   at javax.swing.JToggleButton$ToggleButtonModel.setSelected(JToggleButton.java:237)
   at javax.swing.ButtonGroup.setSelected(ButtonGroup.java:147)
   at org.netbeans.core.multiview.MultiViewModel$BtnGroup.setSelected(MultiViewModel.java:289)
   at javax.swing.JToggleButton$ToggleButtonModel.setSelected(JToggleButton.java:237)
   at javax.swing.AbstractButton.setSelected(AbstractButton.java:329)
   at org.netbeans.core.multiview.TabsComponent.changeActiveManually(TabsComponent.java:216)
   at org.netbeans.core.multiview.MultiViewPeer$MVTCHandler.requestActive(MultiViewPeer.java:703)
   at org.netbeans.core.api.multiview.MultiViewHandler.requestActive(MultiViewHandler.java:95)
   at org.netbeans.modules.xml.schema.multiview.SchemaMultiViewSupport.requestMultiviewActive(SchemaMultiViewSupport.java:175)
   at org.netbeans.modules.xml.schema.multiview.SchemaMultiViewSupport.viewInSwingThread(SchemaMultiViewSupport.java:257)
   at org.netbeans.modules.xml.schema.multiview.SchemaMultiViewSupport.view(SchemaMultiViewSupport.java:228)
   at org.netbeans.modules.xml.schema.actions.SchemaViewOpenAction$1.run(SchemaViewOpenAction.java:90)
   at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:633)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:133)
   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)