只是把答案贴出来，也许是为了帮助别人。简单的解决办法（多亏了三思）是导入“firebase/auth”。下面是一个Firebase文件的例子：

import firebase from 'firebase/app';
import 'firebase/storage';
import "firebase/database";
import "firebase/auth"

 // Initialize Firebase
 var config = {
    apiKey: "*********************",
    authDomain: "...",
    databaseURL: "...",
    projectId: "....",
    storageBucket: "....",
    messagingSenderId: "..."
  };
  firebase.initializeApp(config);

  const storage = firebase.storage();

  export {
      storage, firebase as default
  }

首先检查您的路径是否正确，如果是，尝试删除node_modules文件夹并重新创建npm install！

在较新版本的firebase中，您可以使用firestore、存储或实时数据库的功能

import { initializeApp } from "firebase/app";
import { getFirestore } from "firebase/firestore";
import { getAuth } from "firebase/auth";
// TODO: Add SDKs for Firebase products that you want to use
// https://firebase.google.com/docs/web/setup#available-libraries

// Your web app's Firebase configuration
// For Firebase JS SDK v7.20.0 and later, measurementId is optional
const firebaseConfig = {
  // your firebase configuration
};

// Initialize Firebase
const app = initializeApp(firebaseConfig);
export const firestore = getFirestore(app); //use this for firestore
export const storage = getStorage(app); // use this for storage 
export const auth = getAuth(app);
export default app;