Javascript 如何解决未捕获引用错误：未定义firebase

我正在尝试将firebase分析集成到我的Magento网站中。我在body-end标记之前添加了以下代码

<!-- The core Firebase JS SDK is always required and must be listed first -->
<script src="https://www.gstatic.com/firebasejs/7.11.0/firebase-app.js"></script>

<!-- TODO: Add SDKs for Firebase products that you want to use
     https://firebase.google.com/docs/web/setup#available-libraries -->
<script src="https://www.gstatic.com/firebasejs/7.11.0/firebase-analytics.js"></script>


<script>
  // Your web app's Firebase configuration
  var firebaseConfig = {
  apiKey: "api-key",
  authDomain: "project-id.firebaseapp.com",
  databaseURL: "https://project-id.firebaseio.com",
  projectId: "project-id",
  storageBucket: "project-id.appspot.com",
  messagingSenderId: "sender-id",
  appId: "app-id",
  measurementId: "G-measurement-id",
  };
  // Initialize Firebase
  firebase.initializeApp(firebaseConfig);
  firebase.analytics();
</script>

感谢您的任何帮助

更新

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我尝试运行此代码，但除了firebase凭据之外，还有其他错误。是加载的第一个脚本（它包含全局设置firebase的部分）。

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检查“网络”选项卡，确认请求正常，在重新加载之前禁用缓存，并检查响应是否包含“对象”==typeof self&&self.self==self&&void 0！==self.firebase

或CDN未正确加载，请在网络选项卡Checked中进行检查。js正在加载。这可能会有帮助，然后您必须加载firebase.js。这可能会对您有所帮助。请检查一下。Js正在加载200行吗

Uncaught ReferenceError: firebase is not defined