_unescapeHTML (escapedText) {
    const json = '"' + this._escapeJSON(escapedText) + '"'
    const htmlEscaped = parse(json)

    return htmlEscaped
      .replace(/&lt;/g, '<')
      .replace(/&gt;/g, '>')
      .replace(/&nbsp;|\u00A0/g, ' ')
      .replace(/&amp;/g, '&') // must be replaced last
  }
unescape a string.
@param {String} escapedText
@return {String} text
@private