JavaScript を使用してユーザーのブラウザとそのバージョンを検出および識別するにはどうすればよいですか?

navigator.saysWho = (() => {
  const { userAgent } = navigator;
  let match = userAgent.match(/(opera|chrome|safari|firefox|msie|trident(?=\/))\/?\s*(\d+)/i) || [];
  let temp;

  if (/trident/i.test(match[1])) {
    temp = /\brv[ :]+(\d+)/g.exec(userAgent) || [];

    return `IE ${temp[1] || ''}`;
  }

  if (match[1] === 'Chrome') {
    temp = userAgent.match(/\b(OPR|Edge)\/(\d+)/);

    if (temp !== null) {
      return temp.slice(1).join(' ').replace('OPR', 'Opera');
    }

    temp = userAgent.match(/\b(Edg)\/(\d+)/);

    if (temp !== null) {
      return temp.slice(1).join(' ').replace('Edg', 'Edge (Chromium)');
    }
  }

  match = match[2] ? [match[1], match[2]] : [navigator.appName, navigator.appVersion, '-?'];
  temp = userAgent.match(/version\/(\d+)/i);

  if (temp !== null) {
    match.splice(1, 1, temp[1]);
  }

  return match.join(' ');
})();

console.log(navigator.saysWho); // outputs: `Chrome 89`