Why does startActivityForResult come up as depreciated? how do I fix it?

Question

My app keeps stopping and I am guessing its because of this warning.

startActivityForResult(android.content.Intent, int) is deprecated.

I do not understand why this happens and it's confusing me. Could it be my dependancies?

Screenshot here

public class MainActivity extends AppCompatActivity {

    
    private static final int SIGN_IN_REQUEST_CODE = 123;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        if(FirebaseAuth.getInstance().getCurrentUser() == null) {
            // Start sign in/sign up activity
            startActivityForResult(
                    AuthUI.getInstance()
                            .createSignInIntentBuilder()
                            .build(),
                    SIGN_IN_REQUEST_CODE
            );
        } else {
            // User is already signed in. Therefore, display
            // a welcome Toast
            Toast.makeText(this,
                    "Welcome " + FirebaseAuth.getInstance()
                            .getCurrentUser()
                            .getDisplayName(),
                    Toast.LENGTH_LONG)
                    .show();

            // Load chat room contents
            displayChatMessages();
        }

    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode,
                                    Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if(requestCode == SIGN_IN_REQUEST_CODE) {
            if(resultCode == RESULT_OK) {
                Toast.makeText(this,
                        "Successfully signed in. Welcome!",
                        Toast.LENGTH_LONG)
                        .show();
                displayChatMessages();
            } else {
                Toast.makeText(this,
                        "We couldn't sign you in. Please try again later.",
                        Toast.LENGTH_LONG)
                        .show();

                // Close the app
                finish();
            }
        }

    }
    private void displayChatMessages() {
    }


}