java.lang.NullPointerException: Null child at index 0, parent: Root, model: org.netbeans.spi.viewmodel.Models$CompoundModel@4ea18ffb
  TreeModel = org.netbeans.spi.viewmodel.Models$CompoundTreeModel@217172ed
    org.netbeans.modules.debugger.jpda.projects.ToolTipTreeModelFilter@4c10f433
      org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilter@23a36fdc
        org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilterSI@3f04e6cb
          org.netbeans.spi.viewmodel.Models$DelegatingTreeModel@50f3d011
    org.netbeans.modules.debugger.jpda.models.LocalsTreeModel@10ef2f7
  NodeModel = org.netbeans.spi.viewmodel.Models$CompoundNodeModel@165b0a8d
    org.netbeans.modules.debugger.jpda.projects.ToolTipNodeModelFilter@6d106748
      org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilter@23a36fdc
        org.netbeans.modules.debugger.jpda.ui.models.VariablesNodeModel@7a07e605
        org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilterSI@3f04e6cb
  TableMo
   at org.netbeans.modules.viewmodel.TreeModelNode$TreeModelChildren.applyChildren(TreeModelNode.java:1380)
   at org.netbeans.modules.viewmodel.TreeModelNode$TreeModelChildren.run(TreeModelNode.java:1268)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1418)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1957)