GatewayMessageEventExtraFields

guild_id?: Snowflake;

ID of the guild the message was sent in

member?: Omit<APIGuildMember, 'user'>;

Member properties for this message's author The member object exists in `MESSAGE_CREATE` and `MESSAGE_UPDATE` events from text-based guild channels See https://discord.com/developers/docs/resources/guild#guild-member-object

mentions: (APIUser & {    member?: Omit<APIGuildMember, 'user'>;})[];

Users specifically mentioned in the message The `member` field is only present in `MESSAGE_CREATE` and `MESSAGE_UPDATE` events from text-based guild channels See https://discord.com/developers/docs/resources/user#user-object See https://discord.com/developers/docs/resources/guild#guild-member-object