title: How to determine if a Firebase user is signed in using facebook authentication
body: <p>I am using firebase from google and I have some trouble with user authentication. After logging with facebook I obtain FirebaseUser in AuthStateListener, but how can I detect if this user is logged via facebook or differently?</p>
  
  <p>UPDATE
  As @Frank van Puffelen said FirebaseAuth.getInstance().getCurrentUser().getProviderId()
  should return "facebook", but in my case it returns "firebase". Now I cannot figure out what's the reason of this behavior. When I got FacebookToken I do something like this:</p>
  
  <pre><code>        AuthCredential credential = FacebookAuthProvider.getCredential(facebookToken.getToken());
          mAuth.signInWithCredential(credential)
                  .addOnCompleteListener(this, new OnCompleteListener&lt;AuthResult&gt;() {
                      @Override
                      public void onComplete(@NonNull Task&lt;AuthResult&gt; task) {
  
                          // If sign in fails, display a message to the user. If sign in succeeds
                          // the auth state listener will be notified and logic to handle the
                          // signed in user can be handled in the listener.
                          if (!task.isSuccessful()) {
  
                          }
  
                      }
                  });
  </code></pre>
  
  <p>And afterthat before onComplete() method is called, my AuthStateListener gets user which provider id is not "facebook" as it should be. Am I doing something wrong? I followed official google <a href="https://firebase.google.com/docs/auth/android/facebook-login" rel="noreferrer">documentation</a> </p>