ios – Unhandled Exception: [firebase_auth/invalid-credential] Invalid OAuth response from apple.com

The Resolution I discovered was a single line of code which I added.

// Request credential for the presently signed in Apple account.
remaining appleCredential = await SignInWithApple.getAppleIDCredential(
    scopes: [
        AppleIDAuthorizationScopes.email,
        AppleIDAuthorizationScopes.fullName,
    ],
    nonce: nonce,
);

// Create an `OAuthCredential` from the credential returned by Apple.
remaining oauthCredential = OAuthProvider("apple.com").credential(
    idToken: appleCredential.identityToken,
    rawNonce: rawNonce,
    accessToken: appleCredential.authorizationCode, <-- ADDED THIS LINE
);