code: public function addContent($text)
      {
          if (isset($this->private_content_tag)) {
              $this->private_content_tag->addContent($text);
          } else {
              $this->addContentToAllOpenTags($text);
          }
  
          return true;
      }
docs: Unparsed, but relevant data. The data is added to every open tag.
  
  @param string $text        May include unparsed tags.
  
  @return bool            False on parse error.