https://www.techdirt.com/articles/20210205/15254946196/content-moderation-case-study-twitch-allows-users-to-enable-emote-only-chats-2016.shtml

Summary: Dealing with content moderation during real-time chats always presents an interesting challenge. Whether it’s being able to police language in real time, or dealing with trolling and harassment, chat has always been one of the most difficult content moderation challenges going back to its earliest days.

In 2016, Twitch decided to enable a new feature for its users: an “emote-only” mode for the chat. Emotes, on Twitch, are basically a custom set of what are more traditionally called emoji on most other websites/platforms. With Twitch, though, they are almost entirely custom, and users at certain levels are able to add their own.