/**
  * Will be called before an instance of this block is backed up, so that any links in
  * any links in any HTML fields on config can be encoded.
  * @return string
  */
 function get_backup_encoded_config()
 {
     /// Prevent clone for non configured block instance. Delegate to parent as fallback.
     if (empty($this->config)) {
         return parent::get_backup_encoded_config();
     }
     $data = clone $this->config;
     $data->text = backup_encode_absolute_links($data->text);
     return base64_encode(serialize($data));
 }