customEmojis property
Allows users to send and receive custom emojis.
This adds a set of custom emoji images to the emoji picker, the emoji autocompleter, and emoji reactions.
Every emoji name must start and end with a colon, for example :lol:. Emoji names can be up to 50 characters long, including the colons.
Make sure you always specify a consistent, backward-compatible set of custom emojis. If an existing message contains a custom emoji that is not specified in customEmojis here, then the emoji cannot be displayed and the textual name will be displayed instead (including colons).
If you want to allow an emoji to be displayed if it's used in existing data, but not let users select it in new messages/reactions, set the hidden option to true for that emoji.
Implementation
final CustomEmojis? customEmojis;