Facebook is testing a new reactions feature in Messenger, which would allow users to add reaction emojis next to text in conversations. Users would do this by clicking on a button next to text, which would bring up a series of reactions. The reactions are similar to the current six reaction buttons for posts, but also includes a thumbs down button 👎 (yep, dislike).

The feature also includes a reaction counter, which would list the number of reactions on any given line. The feature doesn’t appear for all users, but the company has conducted tests on small groups of users before rolling it out to the larger population. I hope this feature will also be accessible through Bots API, will be a great replacement of a custom implementation with quick reply buttons.

http://www.theverge.com/2017/3/5/14821874/facebook-testing-reactions-feature-messenger-dislike-button