public function getDefaultAuth(): ?Guard
    {
        // By default, the Auth Facade does not return the
        // any actual authentication guard, but rather an
        // instance of \Illuminate\Auth\AuthManager.
        // Therefore, we make sure only to obtain its
        // "default guard", to make sure that its only the guard
        // instance that we obtain.
        $manager = Auth::getFacadeRoot();
        if (isset($manager)) {
            return $manager->guard();
        }
        return $manager;
    }