Disable Seen By Facebook Notification FOREVER 100% Free

When two or more people chat together, "Seen by" appears when one of the participants views the last message. It nice to know your message has been viewed, but it is also an invasion of privacy. How can I disable "Seen by" so that people do not see "Seen by punch"?

It's that Eazy 
1. You have to Be using Googhe Chrome
2. download This Add on For Ghrome and Install it 

Download Link 
Here

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