Disable Read Receipt FB

While Facebook doesn’t allow you to turn off read receipts, there are third party apps that allow you to set up this feature, allowing you to go undetected on Facebook messages or chats.
The Facebook Unseen add-on for Chrome ensures no one can see whether or not you’ve read their messages, giving you an added layer of privacy and flexibility.
How to do it
1)      Download Facebook Unseen
2)      Once it’s installed, you should see the Facebook Unseen icon in your brower:

3)      Click on the icon to be sure it’s enabled. When it’s working, you should see the following message: