title: Can I authenticate as another user using FirebaseSimpleLogin?
body: <p>Most apps have an "act on behalf of customer X" button. Is that achievable using Firebase?</p>
  
  <p>I noticed I can <a href="https://www.firebase.com/docs/security/custom-login.html" rel="nofollow">create an admin token</a> using a custom login, but since data is inevitably indexed by the user's ID, getting the user's data is difficult if I'm still auth'd as myself.</p>