linkWithCredential with Apple SignIn now possible?

[desmeit]

Here it is described that it is not possible to link credentials from an anonymous user with Apple Sign in. Or only with a trick, if I understand it correctly:
#2048 (comment)

I tried it today with the following plugins:

flutter_login_facebook: ^1.0.1
firebase_core: ^1.0.4
firebase_auth: ^1.1.1

And the following code:

 Future convertWithApple() async {
     final currentUser = _firebaseAuth.currentUser;
    final AuthorizationResult result = await AppleSignIn.performRequests([
      AppleIdRequest(requestedScopes: [Scope.email, Scope.fullName])
    ]);

    switch (result.status) {
      case AuthorizationStatus.authorized:
        final AppleIdCredential _auth = result.credential;
        final OAuthProvider oAuthProvider = new OAuthProvider("apple.com");

        final AuthCredential credential = oAuthProvider.credential(
          idToken: String.fromCharCodes(_auth.identityToken),
          accessToken: String.fromCharCodes(_auth.authorizationCode),
        );

        await currentUser.linkWithCredential(credential);
        await updateUserName(_auth.fullName.givenName, currentUser);

        // update the user information
        if (_auth.fullName != null) {
          await _firebaseAuth.currentUser.updateProfile(
              displayName:
                  "${_auth.fullName.givenName} ${_auth.fullName.familyName}");
        }

        break;

      case AuthorizationStatus.error:
        print("Sign In Failed ${result.error.localizedDescription}");
        break;

      case AuthorizationStatus.cancelled:
        print("User Cancled");
        break;
    }
  }

And it works. It links the anonymous user with Apple. Are there news regarding linkWithCredential and Apple or did I miss something?