re-fix this

Author: ajgeiss0702

src/routes/history/show/[...showDate]/merch-messages/components/MerchMessage.svelte

@@ -20,19 +20,22 @@
 	const seconds = Math.floor(message.timestamp);
 	const imageUrl = `https://merch-message-images.whenplane.com/${message.show}/images/${seconds}.jpg`;
 
-	const floatplaneSeconds = source.startsWith('floatplane')
-		? source === 'floatplane-live'
-			? seconds + 50
-			: seconds
-		: preShowLength !== null
-			? seconds + Math.floor(preShowLength / 1e3)
-			: null;
-	const youtubeSeconds =
+	const floatplaneSeconds = $derived(
+		source.startsWith('floatplane')
+			? source === 'floatplane-live'
+				? seconds + 50
+				: seconds
+			: preShowLength !== null
+				? seconds + Math.floor(preShowLength / 1e3)
+				: null
+	);
+	const youtubeSeconds = $derived(
 		source === 'youtube'
 			? seconds
 			: preShowLength !== null
 				? (floatplaneSeconds ?? seconds) - Math.floor(preShowLength / 1e3)
-				: null;
+				: null
+	);
 </script>
 
 <div