protected function get_output() {

		/**
		 * Filters the user used to retrieve user information displayed by the [llms-user] shortcode
		 *
		 * @since 5.0.0
		 *
		 * @param integer $user_id The WP_User ID of the currently logged-in user or `0` if no user logged in.
		 */
		$user_id = apply_filters( 'llms_user_info_shortcode_user_id', get_current_user_id() );
		$key     = $this->get_attribute( 'key' );
		$default = $this->get_attribute( 'or' );

		if ( in_array( $key, $this->get_blocklist(), true ) ) {
			return '';
		}

		// No user OR no key provided.
		if ( ! $user_id || ! $key ) {
			return $default;
		}

		$user = new WP_User( $user_id );
		$val  = $user->exists() ? $user->get( $key ) : null;

		return ! empty( $val ) && is_scalar( $val ) ? $val : $default;

	}