Facebook does not indicate to users if the other user has deleted any messages. If a user deleted the message without viewing it, it will just display as unread. Ditectly, you can’t. It will only remain unread.

What happens when someone deletes a message on Messenger?

You’ll be asked to confirm that you want to delete the message and, if you do so, your copy of the conversation is permanently erased. The message is then deleted from your copy of the conversation, but it remains in the correspondence of anyone you sent it to.

Can someone see if you delete conversation?

They will not be notified if you deletes a conversation. You can delete your message inbox, not theirs. You can no longer retrieve the messages but the other person still have coversation in his/her inbox until deleted by him/her.

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