public function get_mark_all_discussions_as_read_url(forum_entity $forum) : moodle_url {
        return new moodle_url('/mod/forum/markposts.php', [
            'f' => $forum->get_id(),
            'mark' => 'read',
            'sesskey' => sesskey(),
            'return' => $this->get_forum_view_url_from_forum($forum)->out(),
        ]);
    }