java.util.ConcurrentModificationException
   at java.util.ArrayList$Itr.checkForComodification(ArrayList.java:819)
   at java.util.ArrayList$Itr.next(ArrayList.java:791)
   at org.netbeans.modules.ide.ergonomics.fod.FeatureManager.associateFiles(FeatureManager.java:328)
   at org.netbeans.modules.ide.ergonomics.fod.InstallOrActivateTask.run(InstallOrActivateTask.java:93)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1452)
   at org.openide.util.RequestProcessor$Processor.doEvaluate(RequestProcessor.java:2078)
   at org.openide.util.RequestProcessor$Task.waitFinished(RequestProcessor.java:1686)
   at org.netbeans.modules.ide.ergonomics.fod.FeatureProjectFactory$FeatureNonProject$FeatureOpenHook.run(FeatureProjectFactory.java:442)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1452)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2032)