iCleaner - iOS

請問iCleaner清除message那個選項中

smart 和 on 差在哪裡？

Message attachments (disabled by default):
it deletes files sent and received via iMessage or MMS.
The "smart" setting only deletes files that do not show up in any message
, while "on" deletes all attachments (messages with attachments will show
a blank icon).


on就是把所以附件移除
smart的意思是刪除沒有出現的檔案嗎？這我不太懂

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