how to hide "seen at " when you see message in face book chat without using app :)

how to hide "seen at" when you see message in Facebook chat without using app :)

today i will show to you how hide the "seen" in Facebook without using app or any tools after you seen message sent from your friends at Facebook he or she will see "seen at " in chat

that mean you received and see the message 

now how can do it :

• go to message you want to hide "seen" from it

 and mark as unearned 

• after this step the "seen at" will hide from friend message