Social: render connection template in per-network preview

projects/packages/publicize/_inc/hooks/use-connection-preview-data/index.ts

@@ -103,17 +103,28 @@ export function useConnectionPreviewData( connection: Connection ) {
 
 	return useMemo( () => {
 		const useRendered = templatesEnabled && typeof rendered === 'string';
-		const baseMessage = isPerNetworkMode
-			? ( connection.message ?? globalMessage ).trim()
-			: globalMessage.trim();
+		const hasConnectionMessage = connection.message !== undefined && connection.message !== '';
+		let baseMessage: string;
+		if ( isPerNetworkMode ) {
+			if ( hasConnectionMessage ) {
+				baseMessage = connection.message ?? '';
+			} else if ( templatesEnabled && connection.template ) {
+				baseMessage = connection.template;
+			} else {
+				baseMessage = globalMessage;
+			}
+		} else {
+			baseMessage = globalMessage;
+		}
 
 		return {
 			...postData,
-			message: useRendered ? rendered : baseMessage,
+			message: useRendered ? rendered : baseMessage.trim(),
 			media,
 		};
 	}, [
 		connection.message,
+		connection.template,
 		globalMessage,
 		isPerNetworkMode,
 		media,

projects/packages/publicize/_inc/hooks/use-per-network-customization/index.ts

@@ -50,11 +50,20 @@ export function usePerNetworkCustomization() {
 					featuredImageMime,
 				} );
 
-				customizeConnectionById( connection.connection_id, {
-					message: postMeta.shareMessage || '',
+				/*
+				 * Skip writing `message` when the connection has its own template — leaving
+				 * `connection.message` undefined lets the editor and preview fall back to the
+				 * connection template instead of overwriting it with the global share message.
+				 */
+				const updates: Parameters< typeof customizeConnectionById >[ 1 ] = {
 					attached_media: attachedMedia,
 					media_source: effectiveSource,
-				} );
+				};
+				if ( ! connection.template ) {
+					updates.message = postMeta.shareMessage || '';
+				}
+
+				customizeConnectionById( connection.connection_id, updates );
 			}
 		} );
 	}, [

projects/packages/publicize/_inc/hooks/use-render-message-items/index.ts

@@ -118,11 +118,19 @@ export function useRenderMessageItems(): RenderItem[] {
 
 	const items = useMemo< RenderItem[] >( () => {
 		return connections.map( connection => {
-			const message = ( connection.message ?? globalMessage ?? '' ).trim();
+			const hasConnectionMessage = connection.message !== undefined && connection.message !== '';
+			let raw: string;
+			if ( hasConnectionMessage ) {
+				raw = connection.message ?? '';
+			} else if ( ctx.isPerNetworkMode ) {
+				raw = connection.template ?? globalMessage ?? '';
+			} else {
+				raw = globalMessage ?? '';
+			}
 			return {
 				id: connection.connection_id,
 				network: connection.service_name ?? '',
-				message,
+				message: raw.trim(),
 				is_social_post: connectionHasMedia( connection, ctx ),
 			};
 		} );

projects/packages/publicize/changelog/social-453-per-network-template-render

@@ -0,0 +1,4 @@
+Significance: patch
+Type: fixed
+
+Social: honor per-connection message templates in the per-network preview pipeline and stop overwriting them when toggling per-network mode.