public static function get_metadata(collection $collection) : collection {
        $collection->add_user_preference('block_timeline_user_sort_preference', 'privacy:metadata:timelinesortpreference');
        $collection->add_user_preference('block_timeline_user_filter_preference', 'privacy:metadata:timelinefilterpreference');
        $collection->add_user_preference('block_timeline_user_limit_preference', 'privacy:metadata:timelinelimitpreference');
        return $collection;
    }