org.netbeans.DuplicateException: created from MultiFileObject@1dad1dbf[Modules/slf4j-dummy.xml] is a duplicate of loaded from null
   at org.netbeans.ModuleManager.subCreate(ModuleManager.java:0)
   at org.netbeans.ModuleManager.create(ModuleManager.java:0)
Caused: java.io.IOException: org.netbeans.DuplicateException: created from MultiFileObject@1dad1dbf[Modules/slf4j-dummy.xml] is a duplicate of loaded from null
   at org.netbeans.core.startup.ModuleList.createModule(ModuleList.java:0)
   at org.netbeans.core.startup.ModuleList$Listener.stepCreate(ModuleList.java:0)
   at org.netbeans.core.startup.ModuleList$Listener.access$1300(ModuleList.java:0)
   at org.netbeans.core.startup.ModuleList$Listener$1.run(ModuleList.java:0)
   at org.openide.filesystems.EventControl.runAtomicAction(EventControl.java:0)
   at org.openide.filesystems.FileSystem.runAtomicAction(FileSystem.java:0)
   at org.netbeans.core.startup.ModuleList$Listener.run(ModuleList.java:0)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:0)
   at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:0)
   at org.openide.util.lookup.Lookups.executeWith(Lookups.java:0)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:0)