public function init() {
		if ( ! post_type_exists( $this->post_type ) ) {
			$post_type = register_post_type( $this->post_type, $this->args );
			if ( is_wp_error( $post_type ) ) {
				return $post_type;
			}
		}
		if ( '' !== $this->title_placeholder ) {
			add_filter( 'enter_title_here', array( $this, 'update_placeholder' ) );
		}
	}