code: public void update() {
  
          try {
              String diffHtml = "<pre>" + getDiffHtml() + "</pre>";
              m_diffHtml.setContentMode(ContentMode.HTML);
              m_diffHtml.setValue(diffHtml);
          } catch (Exception e) {
              LOG.error(e.getLocalizedMessage(), e);
          }
  
      }
docs: Updates the displayed diff based on the selected display options.<p>