In Messenger, the message "This person is unavailable on Messenger" will disappear. They will once again see the option to send you a message or see your active status.
If you're concerned about the person finding out that you had blocked them, you may want to consider having a conversation with them about it. However, if you're not ready to have that conversation, unblocking them will not reveal that you had previously blocked them. if i unblock someone on facebook will they know
They might see your interactions on the walls or posts of mutual friends. 2. Changes to Friend Status In Messenger, the message "This person is unavailable
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