java.lang.NullPointerException
        at org.netbeans.modules.css.model.CssModel.updateModel(CssModel.java:313)
        at org.netbeans.modules.css.model.CssModel.<init>(CssModel.java:178)
        at org.netbeans.modules.css.model.CssModel.get(CssModel.java:109)
        at org.netbeans.modules.css.editor.CssEditorSupport.propertyChange(CssEditorSupport.java:260)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:339)
        at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:276)
        at org.openide.text.CloneableEditorSupport.firePropertyChange(CloneableEditorSupport.java:481)
        at org.openide.text.CloneableEditor.componentOpened(CloneableEditor.java:272)
        at org.openide.windows.WindowManager.componentOpenNotify(WindowManager.java:308)
        at org.netbeans.core.windows.WindowManagerImpl.notifyTopComponentOpened(WindowManagerImpl.java:973)
        at org.netbeans.core.windows.Central.addModeOpenedTopComponent(Central.java:759)
        at org.netbeans.core.windows.ModeImpl.addOpenedTopComponent(ModeImpl.java:308)
        at org.netbeans.core.windows.PersistenceHandler.initModeFromConfig(PersistenceHandler.java:393)
        at org.netbeans.core.windows.PersistenceHandler.load(PersistenceHandler.java:210)
        at org.netbeans.core.windows.WindowSystemImpl.load(WindowSystemImpl.java:69)
        at org.netbeans.core.NonGui$3.run(NonGui.java:205)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)