public function __construct() {
		add_filter( 'query_vars', [ $this, 'register_query_vars' ] );
		add_action( 'generate_rewrite_rules', [ $this, 'add_rewrite_rules' ] );
		add_filter( 'post_type_link', [ $this, 'course_content_permalink' ], 1, 2 );
		add_action( 'dozent_option_save_after', [ $this, 'flush_rewrite' ] );
	}