Setting up Amazon Cognito hosted UI using LocalStack and aws sdk

Question

I try to use the Amazon Cognito Hosted UI in my LocalStack cloud emulator. Therefore I set up an userpool and an userpoolclient like this:

 # ----------------------------------------
        # Cognito User Pool
        # ----------------------------------------
        user_pool = cognito.UserPool(self, "CognitoStackUserPool",
            user_pool_name="UserPool",
            standard_attributes={
                "email": {"required": True},
                "fullname": {"required": True}
            },
            self_sign_up_enabled = True,
            auto_verify= {"email": True},
        )


        # ----------------------------------------
        # Cognito App Client
        # ----------------------------------------
        app_client = cognito.UserPoolClient(
            self,
            "CognitoStackUserClient",
            user_pool_client_name="UserPoolClient",
            user_pool=user_pool,
        )

When I now access the Cognito hosted UI to test the sign up/sign in process the email field doesn't appear at the sign up, although I set:

 "email": {"required": True}

Does anybody know if there is a issue with the Cognito hosted UI in LocalStack? The sign up process fails because I didn't provide an email address (but how could I with no input field)