java.lang.AssertionError
   at org.netbeans.modules.xml.xdm.XDMModel.<init>(XDMModel.java:100)
   at org.netbeans.modules.xml.xdm.xam.XDMAccess.<init>(XDMAccess.java:85)
   at org.netbeans.modules.xml.xdm.xam.XDMAccessProvider.createModelAccess(XDMAccessProvider.java:69)
   at org.netbeans.modules.xml.xam.dom.AbstractDocumentModel.getAccess(AbstractDocumentModel.java:521)
   at org.netbeans.modules.xml.xam.dom.AbstractDocumentModel.getAccess(AbstractDocumentModel.java:76)
   at org.netbeans.modules.xml.xam.AbstractModel.isAutoSyncActive(AbstractModel.java:640)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.AssertionError
   at org.openide.util.RequestProcessor$Task.schedule(RequestProcessor.java:1451)
   at org.netbeans.modules.xml.xam.AbstractModelFactory$1.run(AbstractModelFactory.java:167)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1413)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1952)