Reactions will have 4 new faces- tears of joy, thinking face, clapping hands and crying face. This feature is designed to give users the ability to better show how conversations make them feel.
If users see a reply that doesn’t seem relevant to the conversation, they can downvote it. Downvotes aren’t public and won’t be shared with the Tweet author or others on the timeline. Twitter says that downvotes will help prioritize higher quality content for everyone on Twitter.
Users will be able to decide whether they want to receive all replies or just the ones relevant.
Relevant to you: Replies from people you follow and other replies likely to be most interesting to you;
All Replies: All replies, including those that may be potentially smappy, harmful, or offensive.