renderIntoDomNode example

          // media (or if the media entity can't be loaded, the missing media           // indicator). But, we need to merge in CSS classes added by other           // filters, such as filter_align, in order for those filters to work           // properly.           $build['#attributes']['class'] = array_unique(array_merge($build['#attributes']['class'], explode(' ', $attribute->nodeValue)));
        }
        else {
          $build['#attributes'][$attribute->nodeName] = $attribute->nodeValue;
        }
      }

      $this->renderIntoDomNode($build, $node, $result);
    }

    $result->setProcessedText(Html::serialize($dom));

    return $result;
  }

  /** * {@inheritdoc} */
  public function tips($long = FALSE) {