protected function load_standard_tags() {
        global $CFG, $DB;
        if (!$this->is_tagging_enabled()) {
            return array();
        }
        $namefield = empty($CFG->keeptagnamecase) ? 'name' : 'rawname';
        $tags = $DB->get_records_menu('tag',
            array('isstandard' => 1, 'tagcollid' => $this->get_tag_collection()),
            $namefield, 'id,' . $namefield);
        return array_combine($tags, $tags);
    }