Support channel follow messages

src/d2m/converters/message-to-event.js

@@ -357,6 +357,17 @@ async function messageToEvent(message, guild, options = {}, di) {
 		}]
 	}
 
+	if (message.type === DiscordTypes.MessageType.ChannelFollowAdd) {
+		return [{
+			$type: "m.room.message",
+			msgtype: "m.emote",
+			body: `set this room to receive announcements from ${message.content}`,
+			format: "org.matrix.custom.html",
+			formatted_body: tag`set this room to receive announcements from <strong>${message.content}</strong>`,
+			"m.mentions": {}
+		}]
+	}
+
 	let isInteraction = (message.type === DiscordTypes.MessageType.ChatInputCommand || message.type === DiscordTypes.MessageType.ContextMenuCommand) && message.interaction && "name" in message.interaction
 	let isThinkingInteraction = isInteraction && !!((message.flags || 0) & DiscordTypes.MessageFlags.Loading)
 

src/d2m/converters/message-to-event.test.js

@@ -1142,6 +1142,19 @@ test("message2event: type 4 channel name change", async t => {
 	}])
 })
 
+test("message2event: type 12 channel follow add", async t => {
+	const events = await messageToEvent(data.special_message.channel_follow_add, data.guild.general)
+	t.deepEqual(events, [{
+		$type: "m.room.message",
+		"m.mentions": {},
+		msgtype: "m.emote",
+		body: "set this room to receive announcements from PluralKit #downtime",
+		format: "org.matrix.custom.html",
+		formatted_body: "set this room to receive announcements from <strong>PluralKit #downtime</strong>",
+		"m.mentions": {}
+	}])
+})
+
 test("message2event: thread start message reference", async t => {
 	const events = await messageToEvent(data.special_message.thread_start_context, data.guild.general, {}, {
 		api: {

test/data.js

@@ -6170,6 +6170,37 @@ module.exports = {
 			components: [],
 			position: 12
 		},
+		channel_follow_add: {
+			type: 12,
+			content: "PluralKit #downtime",
+			attachments: [],
+			embeds: [],
+			timestamp: "2026-03-24T23:16:04.097Z",
+			edited_timestamp: null,
+			flags: 0,
+			components: [],
+			id: "1486141581047369888",
+			channel_id: "1451125453082591314",
+			author: {
+				id: "154058479798059009",
+				username: "exaptations",
+				discriminator: "0",
+				avatar: "57b5cfe09a48a5902f2eb8fa65bb1b80",
+				bot: false,
+				flags: 0,
+				globalName: "Exa",
+			},
+			pinned: false,
+			mentions: [],
+			mention_roles: [],
+			mention_everyone: false,
+			tts: false,
+			message_reference: {
+				type: 0,
+				channel_id: "1015204661701124206",
+				guild_id: "466707357099884544"
+			}
+		},
 		updated_to_start_thread_from_here: {
 			t: "MESSAGE_UPDATE",
 			s: 19,