title: firebase.initializeApp is not a function
body: <p>I'm trying to make a site in React, and I have added the Firebase library using <code>npm i firebase --save</code></p>
  
  <p>I am then trying to call this in my app, but I am not having much joy:</p>
  
  <pre><code>import * as firebase from "firebase";
  
  const instance = firebase.initializeApp({
    apiKey: '123',
    authDomain: 'https://123.firebaseapp.com/',
    databaseURL: 'https://123.firebaseio.com/'
  });
  
  export default instance;
  </code></pre>
  
  <p>No matter what I try, it throws:</p>
  
  <blockquote>
    <p>firebase.initializeApp is not a function</p>
  </blockquote>
  
  <p>I've checked its in my node_modules and i've reinstalled it, but I still have no such luck.</p>
  
  <p>Any suggestions?</p>