private String headHtml;
    private String headerHtml;
    private String footerHtml;


    @Override
    public void register(Asciidoctor asciidoctor) {
        initializeHtmlToInject();

        JavaExtensionRegistry registry = asciidoctor.javaExtensionRegistry();

        registry.docinfoProcessor(new NavigationDocinfoProcessor(new HashMap<>(), headHtml));