protected static function export_tracking_data(int $userid, \stdClass $forum, int $tracked) {
        if (null !== $tracked) {
            // The user has a main preference to track all forums, but has opted out of this one.
            writer::with_context(\context_module::instance($forum->cmid))
                ->export_metadata([], 'trackreadpreference', 0, get_string('privacy:readtrackingdisabled', 'mod_forum'));

            return true;
        }

        return false;
    }