fix: flatten carousel thumbnail fallback

src/Socket/messages-send.ts

@@ -682,6 +682,33 @@ export const makeMessagesSocket = (config: SocketConfig) => {
 		return false
 	}
 
+	const canonicalizeCarouselRecipients = async (recipientJids: string[]) => {
+		const uniqueRecipients = [...new Set(recipientJids)]
+		const pnRecipients = uniqueRecipients.filter(jid => isPnUser(jid) || isHostedPnUser(jid))
+		const lidMappings = pnRecipients.length > 0
+			? await signalRepository.lidMapping.getLIDsForPNs(pnRecipients)
+			: []
+
+		const lidByPn = new Map((lidMappings || []).map(({ pn, lid }) => [pn, lid]))
+		const canonicalRecipients: string[] = []
+
+		for (const jid of uniqueRecipients) {
+			const canonicalJid = lidByPn.get(jid) || jid
+			if (!canonicalRecipients.includes(canonicalJid)) {
+				canonicalRecipients.push(canonicalJid)
+			}
+		}
+
+		if (canonicalRecipients.length !== uniqueRecipients.length || canonicalRecipients.some((jid, index) => jid !== uniqueRecipients[index])) {
+			logger.debug(
+				{ before: uniqueRecipients, after: canonicalRecipients },
+				'[CAROUSEL] Canonicalized recipient addressing for session reuse'
+			)
+		}
+
+		return canonicalRecipients
+	}
+
 	const relayMessage = async (
 		jid: string,
 		message: proto.IMessage,
@@ -968,21 +995,30 @@ export const makeMessagesSocket = (config: SocketConfig) => {
 					allRecipients.push(jid)
 				}
 
-				await assertSessions(allRecipients)
+				const isCarouselFanout = isCarouselMessage(message)
+				const effectiveMeRecipients = isCarouselFanout
+					? await canonicalizeCarouselRecipients(meRecipients)
+					: meRecipients
+				const effectiveOtherRecipients = isCarouselFanout
+					? await canonicalizeCarouselRecipients(otherRecipients)
+					: otherRecipients
+				const effectiveAllRecipients = [...effectiveMeRecipients, ...effectiveOtherRecipients]
+
+				await assertSessions(effectiveAllRecipients)
 
 				const [
 					{ nodes: meNodes, shouldIncludeDeviceIdentity: s1 },
 					{ nodes: otherNodes, shouldIncludeDeviceIdentity: s2 }
 				] = await Promise.all([
 					// For own devices: use DSM if available (1:1 chats only)
-					createParticipantNodes(meRecipients, meMsg || message, extraAttrs),
+					createParticipantNodes(effectiveMeRecipients, meMsg || message, extraAttrs),
-					createParticipantNodes(otherRecipients, message, extraAttrs, meMsg)
+					createParticipantNodes(effectiveOtherRecipients, message, extraAttrs, meMsg)
 				])
 				participants.push(...meNodes)
 				participants.push(...otherNodes)
 
-				if (meRecipients.length > 0 || otherRecipients.length > 0) {
+				if (effectiveMeRecipients.length > 0 || effectiveOtherRecipients.length > 0) {
-					extraAttrs['phash'] = generateParticipantHashV2([...meRecipients, ...otherRecipients])
+					extraAttrs['phash'] = generateParticipantHashV2([...effectiveMeRecipients, ...effectiveOtherRecipients])
 				}
 
 				shouldIncludeDeviceIdentity = shouldIncludeDeviceIdentity || s1 || s2

src/Utils/messages.ts

@@ -41,10 +41,12 @@ import type { ILogger } from './logger'
 import {
 	downloadContentFromMessage,
 	encryptedStream,
+	extractImageThumb,
 	generateThumbnail,
 	getAudioDuration,
 	getAudioWaveform,
 	getRawMediaUploadData,
+	getStream,
 	type MediaDownloadOptions
 } from './messages-media'
 import { shouldIncludeReportingToken } from './reporting-utils'
@@ -473,6 +475,48 @@ export const formatNativeFlowButton = (button: NativeButton): NativeFlowButton =
 	}
 }
 
+const recoverCarouselImageMetadata = async (
+	card: CarouselMessageOptions['cards'][number],
+	imageMessage: proto.Message.IImageMessage,
+	mediaOptions: MessageContentGenerationOptions
+) => {
+	if (imageMessage.jpegThumbnail && imageMessage.height && imageMessage.width) {
+		return
+	}
+
+	try {
+		const { stream } = await getStream(card.image!, mediaOptions.options)
+		const thumb = await extractImageThumb(stream)
+
+		if (!imageMessage.jpegThumbnail) {
+			imageMessage.jpegThumbnail = thumb.buffer
+		}
+
+		if (!imageMessage.width && thumb.original.width) {
+			imageMessage.width = thumb.original.width
+		}
+
+		if (!imageMessage.height && thumb.original.height) {
+			imageMessage.height = thumb.original.height
+		}
+
+		mediaOptions.logger?.info(
+			{
+				cardTitle: card.title,
+				hasJpegThumbnail: !!imageMessage.jpegThumbnail,
+				width: imageMessage.width,
+				height: imageMessage.height
+			},
+			'[CAROUSEL] Recovered image thumbnail/dimensions from source media'
+		)
+	} catch (error) {
+		mediaOptions.logger?.warn(
+			{ cardTitle: card.title, error },
+			'[CAROUSEL] Failed to recover image thumbnail/dimensions from source media'
+		)
+	}
+}
+
 /**
  * Generates a button message using Native Flow format wrapped in viewOnceMessage
  * This is the modern approach for button messages that works on iOS and Android
@@ -648,7 +692,10 @@ export const generateCarouselMessage = async (
 			if (hasMedia && mediaOptions) {
 				if (card.image) {
 					const { imageMessage } = await prepareWAMessageMedia({ image: card.image }, mediaOptions)
-					// Validate image fields needed for WhatsApp rendering
+					if (imageMessage) {
+						await recoverCarouselImageMetadata(card, imageMessage, mediaOptions)
+					}
+
 					if (imageMessage && !imageMessage.jpegThumbnail) {
 						mediaOptions.logger?.warn(
 							{ cardTitle: card.title },