this extension doesnt work in messenger.com and other sites where the input field is heavily scripted but a hack has been used to make it work on facebook.com. other than that it should work in sites with simple html input fields.
It uses AES encryption method ( implementation of Crypto-js ) to encrypt your messages using a secret/password that you provide. If you click on the extension icon you'll have a text input box to enter your secret - You have to enter the password there and the extension will use it for further encryptions. You can also uncheck the extension active checkbox to disable the extension.
Follow this guide to install the extension
https://dev.to/ben/how-to-install-chrome-extensions-manually-from-github-1612
If your press ctrl+alt+q after you write something on the text input field of chatbox the text will automatically get replaced by the encrypted text.
| Before Encryption | After pressing ctrl+alt+q |
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After you send the encrypted text, facebook will send the encrypted texts to the receipent. Then the receipent will have to press ctrl+q to decrypt all the encrypted texts on screen.
| Before Decryption | After pressing ctrl+q |
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