title: Can't access the firebase object
body: <p>I can see I've the script in the <code>head</code>, I get this error &quot;error. 'firebase' is not defined (no-undef)&quot;. Why can't I use the firebase object?</p>
  <pre><code>mounted() {
    let recaptchaScript = document.createElement('script');
    recaptchaScript.setAttribute(
      'src',
      'https://www.gstatic.com/firebasejs/7.17.1/firebase-app.js'
    );
    document.head.appendChild(recaptchaScript);
  
    console.log('firebase is: ', firebase);
  
    // this.initFirebase();
  },
  </code></pre>