universal-firebase-auth/src/firebase.js

A reusable Firebase-based authentication package like Clerk for React with social login support (Google, Facebook, GitHub, LinkedIn, etc).

import { initializeApp, getApps } from "firebase/app";
import { getAuth } from "firebase/auth";

export const initFirebase = (config) => {
  if (!getApps().length) {
    initializeApp(config);
  }
  return getAuth();
};