java.lang.IllegalStateException: Too many org.netbeans.modules.xml.schema.SchemaEditorSupport$4 (3) in shared RequestProcessor; create your own
   at org.openide.util.RequestProcessor.post(RequestProcessor.java:422)
   at org.netbeans.modules.xml.schema.SchemaEditorSupport.syncModel(SchemaEditorSupport.java:610)
   at org.netbeans.modules.xml.schema.multiview.SchemaSourceMultiViewElement.componentHidden(SchemaSourceMultiViewElement.java:328)
   at org.netbeans.core.multiview.MultiViewPeer.hideElement(MultiViewPeer.java:262)
   at org.netbeans.core.multiview.MultiViewPeer$SelectionListener.selectionChanged(MultiViewPeer.java:678)
   at org.netbeans.core.multiview.MultiViewModel.fireSelectionChanged(MultiViewModel.java:246)
   at org.netbeans.core.multiview.MultiViewModel.setActiveDescription(MultiViewModel.java:118)
   at org.netbeans.core.multiview.MultiViewModel$BtnGroup.setSelected(MultiViewModel.java:296)
   at javax.swing.JToggleButton$ToggleButtonModel.setSelected(JToggleButton.java:237)
   at javax.swing.ButtonGroup.setSelected(ButtonGroup.java:147)
   at org.netbeans.core.multiview.MultiViewModel$BtnGroup.setSelected(MultiViewModel.java:292)
   at javax.swing.JToggleButton$ToggleButtonModel.setSelected(JToggleButton.java:237)
   at javax.swing.AbstractButton.setSelected(AbstractButton.java:329)
   at org.netbeans.core.multiview.TabsComponent.changeActiveManually(TabsComponent.java:219)
   at org.netbeans.core.multiview.MultiViewPeer$MVTCHandler.requestActive(MultiViewPeer.java:706)
   at org.netbeans.core.api.multiview.MultiViewHandler.requestActive(MultiViewHandler.java:98)
   at org.netbeans.modules.xml.schema.multiview.SchemaMultiViewSupport.requestMultiviewActive(SchemaMultiViewSupport.java:178)
   at org.netbeans.modules.xml.schema.multiview.SchemaMultiViewSupport.viewInSwingThread(SchemaMultiViewSupport.java:260)
   at org.netbeans.modules.xml.schema.multiview.SchemaMultiViewSupport.view(SchemaMultiViewSupport.java:231)
   at org.netbeans.modules.xml.schema.actions.SchemaViewOpenAction$1.run(SchemaViewOpenAction.java:93)
   at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
   at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
   at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:137)
   at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
   at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
   at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
   at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
   at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)