java.lang.NullPointerException
        at org.netbeans.modules.visualweb.designer.cssengine.CssEngineServiceImpl.getBackgroundImageUrlForElement(CssEngineServiceImpl.java:1069)
        at org.netbeans.modules.visualweb.css.CssBox.initializeBackgroundImage(CssBox.java:485)
        at org.netbeans.modules.visualweb.css.CssBox.initializeBackground(CssBox.java:462)
        at org.netbeans.modules.visualweb.css.ContainerBox.initializeBackground(ContainerBox.java:150)
        at org.netbeans.modules.visualweb.css.PageBox.initializeBackground(PageBox.java:1155)
        at org.netbeans.modules.visualweb.css.CssBox.initializeInvariants(CssBox.java:309)
        at org.netbeans.modules.visualweb.css.CssBox.<init>(CssBox.java:251)
        at org.netbeans.modules.visualweb.css.ContainerBox.<init>(ContainerBox.java:97)
        at org.netbeans.modules.visualweb.css.DocumentBox.<init>(DocumentBox.java:106)
        at org.netbeans.modules.visualweb.css.PageBox.<init>(PageBox.java:112)
        at org.netbeans.modules.visualweb.css.PageBox.<init>(PageBox.java:105)
        at org.netbeans.modules.visualweb.css.PageBox.getPageBox(PageBox.java:139)
        at org.netbeans.modules.visualweb.designer.DesignerPaneUI.resetPageBox(DesignerPaneUI.java:630)
        at org.netbeans.modules.visualweb.designer.WebForm.resetPanePageBox(WebForm.java:2779)
        at org.netbeans.modules.visualweb.designer.jsf.ui.JsfTopComponent.resetDesigner(JsfTopComponent.java:2731)
        at org.netbeans.modules.visualweb.designer.jsf.ui.JsfTopComponent.designerShowing(JsfTopComponent.java:2702)
        at org.netbeans.modules.visualweb.designer.jsf.ui.JsfTopComponent.modelLoaded(JsfTopComponent.java:2767)
        at org.netbeans.modules.visualweb.designer.jsf.ui.JsfMultiViewElement.modelLoaded(JsfMultiViewElement.java:243)
        at org.netbeans.modules.visualweb.designer.jsf.JsfForm.notifyViewsModelLoaded(JsfForm.java:3029)
        at org.netbeans.modules.visualweb.designer.jsf.JsfForm.access$300(JsfForm.java:131)
        at org.netbeans.modules.visualweb.designer.jsf.JsfForm$$.run(JsfForm.java:375)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:104)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:284)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)