我正在尝试使用react进行firebase email/password auth，但出现了一个错误：
“_firebaseWEBPACK_IMPORTED_MODULE_1.default.onAuthStateChanged不是函数TypeError：_firebaseWEBPACK_IMPORTED_MODULE_1.default.onAuthStateChanged不是函数”
所以我想我的AuthContext.js代码一定有问题：

import React, { useContext, useState, useEffect } from "react";
import auth from "../firebase";

const AuthContext = React.createContext();

export function useAuth() {
  return useContext(AuthContext);
}

export function AuthProvider({ children }) {
  const [currentUser, setCurrentUser] = useState();
  const [loading, setLoading] = useState(true);

  function signup(email, password) {
    return auth.createUserWithEmailAndPassword(email, password);
  }

  function login(email, password) {
    return auth.signInWithEmailAndPassword(email, password);
  }

  useEffect(() => {
    const unsubscribe = auth.onAuthStateChanged((user) => {
      setCurrentUser(user);
      setLoading(false);
    });

    return unsubscribe;
  }, []);

  const value = {
    currentUser,
    login,
    signup,
  };

  return (
    <AuthContext.Provider value={value}>
      {!loading && children}
    </AuthContext.Provider>
  );
}

我花了三个小时才找到解决办法。可惜没有成功：（