moodle 有email通知功能，居然要額外安裝測試外掛

只好安裝，才能測試是否設定成功

https://moodle.org/plugins/local_mailtest?nonjscomment=1&comment_itemid=1527&comment_context=50&comment_component=local_plugins&comment_area=plugin_general&comment_page=1

當然通知是可以關閉的

Administration -> General -> Messaging -> Notification settings