Remove rather than truncate links in reply preview

src/m2d/converters/event-to-message.js

@@ -773,14 +773,14 @@ async function eventToMessage(event, guild, channel, di) {
 				repliedToEvent.content = repliedToEvent.content["m.new_content"]
 			}
 			/** @type {string} */
-			let repliedToContent = repliedToEvent.content.formatted_body || repliedToEvent.content.body
+			let originalRepliedToContent = repliedToEvent.content.formatted_body || repliedToEvent.content.body
 			const fileReplyContentAlternative = attachmentEmojis.get(repliedToEvent.content.msgtype)
 			let contentPreview
 			if (fileReplyContentAlternative) {
 				contentPreview = " " + fileReplyContentAlternative
 			} else if (repliedToEvent.unsigned?.redacted_because) {
 				contentPreview = " (in reply to a deleted message)"
-			} else if (typeof repliedToContent !== "string") {
+			} else if (typeof originalRepliedToContent !== "string") {
 				// in reply to a weird metadata event like m.room.name, m.room.member...
 				// I'm not implementing text fallbacks for arbitrary room events. this should cover most cases
 				// this has never ever happened in the wild anyway
@@ -788,6 +788,7 @@ async function eventToMessage(event, guild, channel, di) {
 				contentPreview = " (channel details edited)"
 			} else {
 				// Generate a reply preview for a standard message
+				let repliedToContent = originalRepliedToContent
 				repliedToContent = repliedToContent.replace(/.*<\/mx-reply>/s, "") // Remove everything before replies, so just use the actual message body
 				repliedToContent = repliedToContent.replace(/^\s*<blockquote>.*?<\/blockquote>(.....)/s, "$1") // If the message starts with a blockquote, don't count it and use the message body afterwards
 				repliedToContent = repliedToContent.replace(/(?:\n|<br ?\/?>)+/g, " ") // Should all be on one line
@@ -802,7 +803,18 @@ async function eventToMessage(event, guild, channel, di) {
 				const contentPreviewChunks = chunk(repliedToContent, 50)
 				if (contentPreviewChunks.length) {
 					contentPreview = ": " + contentPreviewChunks[0]
-					contentPreview = contentPreview.replace(/\bhttps?:\/\/[^ )]*/g, "<$&>")
+					contentPreview = contentPreview.replace(/\bhttps?:\/\/[^ )]*/g, url => {
+						const originalUrlIndex = originalRepliedToContent.indexOf(url)
+						if (originalUrlIndex !== -1 && originalRepliedToContent[originalUrlIndex + url.length]?.match(/[^ )>"'`]/)) { // URL was truncated by chunking, replace it
+							try {
+								const u = new URL(url)
+								return `<via ${u.hostname}>`
+							} catch (e) {
+								return `<url>`
+							}
+						}
+						return `<${url}>` // Full URL is present, escape it
+					})
 					if (contentPreviewChunks.length > 1) contentPreview = contentPreview.replace(/[,.']$/, "") + "..."
 				} else {
 					contentPreview = ""

src/m2d/converters/event-to-message.test.js

@@ -2117,6 +2117,57 @@ test("event2message: should suppress embeds for links in reply preview", async t
 	)
 })
 
+test("event2message: truncated links in reply preview should be unlinked to prevent broken links", async t => {
+	t.deepEqual(
+		await eventToMessage({
+			type: "m.room.message",
+			sender: "@cadence:cadence.moe",
+			content: {
+				msgtype: "m.text",
+				body: `> <@_ooye_.wing.:cadence.moe> https://huggingface.co/blog/security-incident-july-2026\n\nthis is either written by claude or somebody who's too claude-brained and I just can't get through it`,
+				format: "org.matrix.custom.html",
+				formatted_body: `<mx-reply><blockquote><a href="https://matrix.to/#/!fGgIymcYWOqjbSRUdV:cadence.moe/$qmyjr-ISJtnOM5WTWLI0fT7uSlqRLgpyin2d2NCglCU?via=cadence.moe">In reply to</a> <a href="https://matrix.to/#/@_ooye_.wing.:cadence.moe">@_ooye_.wing.:cadence.moe</a><br>https://huggingface.co/blog/security-incident-july-2026</blockquote></mx-reply>this is either written by claude or somebody who's too claude-brained and I just can't get through it`,
+				"m.relates_to": {
+					"m.in_reply_to": {
+						event_id: "$qmyjr-ISJtnOM5WTWLI0fT7uSlqRLgpyin2d2NCglCU"
+					}
+				}
+			},
+			event_id: "$0Bs3rbsXaeZmSztGMx1NIsqvOrkXOpIWebN-dqr09i4",
+			room_id: "!fGgIymcYWOqjbSRUdV:cadence.moe"
+		}, data.guild.general, data.channel.general, {
+			api: {
+				getEvent: mockGetEvent(t, "!fGgIymcYWOqjbSRUdV:cadence.moe", "$qmyjr-ISJtnOM5WTWLI0fT7uSlqRLgpyin2d2NCglCU", {
+					"type": "m.room.message",
+					"sender": "@_ooye_.wing.:cadence.moe",
+					"content": {
+						"m.mentions": {},
+						"msgtype": "m.text",
+						"body": "<https://huggingface.co/blog/security-incident-july-2026>",
+						"format": "org.matrix.custom.html",
+						"formatted_body": "<a href=\"https://huggingface.co/blog/security-incident-july-2026\">https://huggingface.co/blog/security-incident-july-2026</a>"
+					}
+				})
+			}
+		}),
+		{
+			ensureJoined: [],
+			messagesToDelete: [],
+			messagesToEdit: [],
+			messagesToSend: [{
+				username: "cadence [they]",
+				content: "-# > <:L1:1144820033948762203><:L2:1144820084079087647>https://discord.com/channels/112760669178241024/687028734322147344/1273204543739396116 <@112890272819507200>:"
+					+ " <via huggingface.co>..."
+					+ `\nthis is either written by claude or somebody who's too claude-brained and I just can't get through it`,
+				avatar_url: "https://bridge.example.org/download/matrix/cadence.moe/azCAhThKTojXSZJRoWwZmhvU?preset=avatar",
+				allowed_mentions: {
+					parse: ["users", "roles"]
+				}
+			}]
+		}
+	)
+})
+
 test("event2message: should include a reply preview when message ends with a blockquote", async t => {
 	t.deepEqual(
 		await eventToMessage({