java.lang.NullPointerException
   at org.netbeans.modules.debugger.ui.views.ViewModelListener.joinLists(ViewModelListener.java:442)
   at org.netbeans.modules.debugger.ui.views.ViewModelListener.refreshModel(ViewModelListener.java:460)
   at org.netbeans.modules.debugger.ui.views.ViewModelListener.access$1600(ViewModelListener.java:116)
   at org.netbeans.modules.debugger.ui.views.ViewModelListener$ModelsChangeRefresher.run(ViewModelListener.java:793)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.NullPointerException
   at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:1459)
   at org.netbeans.modules.debugger.ui.views.ViewModelListener$ModelsChangeRefresher.propertyChange(ViewModelListener.java:789)
   at org.netbeans.api.debugger.Lookup$Compound$CompoundLookupList.propertyChange(Lookup.java:214)
   at org.netbeans.api.debugger.Lookup$Compound$CompoundLookupList.propertyChange(Lookup.java:214)
   at org.netbeans.api.debugger.Lookup$Compound$CompoundLookupList.propertyChange(Lookup.java:214)
   at org.netbeans.api.debugger.Lookup$Compound$CompoundLookupList.propertyChange(Lookup.java:214)
   at org.netbeans.api.debugger.Lookup$MetaInf$MetaInfLookupList.firePropertyChange(Lookup.java:692)
   at org.netbeans.api.debugger.Lookup$MetaInf$MetaInfLookupList.refreshContent(Lookup.java:641)
   at org.netbeans.api.debugger.Lookup$MetaInf$MetaInfLookupList.access$100(Lookup.java:497)
   at org.netbeans.api.debugger.Lookup$MetaInf.refreshLists(Lookup.java:411)
   at org.netbeans.api.debugger.Lookup$MetaInf.access$600(Lookup.java:220)
   at org.netbeans.api.debugger.Lookup$MetaInf$ModuleChangeListener$1.run(Lookup.java:461)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1418)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1960)