code: public void setHeaderVisible(boolean visible) {
  
          String style = I_CmsSitemapLayoutBundle.INSTANCE.sitemapCss().headerContainerVaadinMode();
          if (visible) {
              m_headerContainer.removeStyleName(style);
          } else {
              m_headerContainer.addStyleName(style);
          }
      }
docs: Sets the visibility of the normal siteamp header (the header can be hidden so that the Vaadin code can display its own header).<p>
  
  @param visible true if the normal header should be visible