public function diag_strings() {
        $sm = get_string_manager();
        if (!$sm->string_exists($this->identifier, $this->component)) {
            debugging("Help title string does not exist: [$this->identifier, $this->component]");
        }
        if (!$sm->string_exists($this->identifier.'_help', $this->component)) {
            debugging("Help contents string does not exist: [{$this->identifier}_help, $this->component]");
        }
    }