title: Error trying to login in with Firebase with Facebook Sign In Credential
body: <h1>Objective</h1>
  
  <p>Integrate Facebook Login to my Flutter app. Manage to integrate it with the existing Firebase 
  configuration (Google Sign In Auth and Firestore Database). </p>
  
  <h1>Step by Step to reproduce my error:</h1>
  
  <p>1) I have created a new app on Facebook Developers and follow up the step by step to configure my app to call the Facebook Login (add what is needed to strings.xml and to AndroidManifest)</p>
  
  <p>2) Go to Firebase Console, activate the Facebook Sign In option and add App Id and App secret with the same info added to the app.</p>
  
  <p>3) Return to Facebook Developer and edit Facebook Login > Configuration to add the </p>
  
  <blockquote>
    <p><a href="https://myappname.firebaseapp.com/__/auth/handler" rel="nofollow noreferrer">https://myappname.firebaseapp.com/__/auth/handler</a></p>
  </blockquote>
  
  <p>into the OAuth valid redirects.</p>
  
  <p>3) Add the package flutter_facebook_login: ^1.1.1 to flutter and update packages
  4) Implement the following code to be call on a material button onPress:</p>
  
  <pre><code> final _facebookLogin = FacebookLogin();
   Future&lt;FirebaseUser&gt; facebookSignIn() async {
      loading.add(true);
      final result = await _facebookLogin.logInWithReadPermissions(['email']);
  
      if(result.status == FacebookLoginStatus.loggedIn) {
        final AuthCredential credential = FacebookAuthProvider.getCredential(
            accessToken: result.accessToken.token
        );
  
        final AuthResult authResult = await _auth.signInWithCredential(credential);
        final FirebaseUser user = authResult.user;
  
        updateUserData(user);
        print("sign in " + user.displayName);
  
        return user;
      }
  
      loading.add("false");
      return null;
    }
  </code></pre>
  
  <p>6) Receive this error:</p>
  
  <blockquote>
    <p>E/flutter (22866): [ERROR:flutter/lib/ui/ui_dart_state.cc(157)]
    Unhandled Exception: PlatformException(ERROR_INVALID_CREDENTIAL, The
    supplied auth credential is malformed or has expired. [ Unsuccessful
    debug_token response from Facebook: {"error":{"message":"Invalid OAuth
    access token
    signature.","type":"OAuthException","code":190,"fbtrace_id":"MY_FB_TRACE_ID"}}
    ], null)</p>
  </blockquote>
  
  <p>This error, as I searched about is something wrong with the OAuth configuration on step 3, but I returned and check multiple times.</p>
  
  <p>Does anyone knows if there is another thing I must check to make this work?</p>