code: public String toHtmlString() {
          initAbstractHtml();
          wsWarningDisabled = true;
          beforeToHtml(rootTag);
          wsWarningDisabled = false;
          final String htmlString = rootTag.toHtmlString(true);
          wsWarningDisabled = true;
          afterToHtml(rootTag);
          wsWarningDisabled = false;
          return htmlString;
      }
docs: NB: this method should not be called under {@link BrowserPage#render()}
  method because this method internally calls {@link BrowserPage#render()}
  method.
  
  @return {@code String} equalent to the html string of the tag including
  the child tags.
  
  @author WFF