diff --git a/web/src/submessage.ts b/web/src/submessage.ts
index 7b754b9886..1e2500bf51 100644
--- a/web/src/submessage.ts
+++ b/web/src/submessage.ts
@@ -90,8 +90,9 @@ export function get_message_events(message: Message): SubmessageEvents | undefin
 
 export function process_widget_rows_in_list(list: MessageList | undefined): void {
     for (const message_id of widgetize.widget_event_handlers.keys()) {
-        if (list?.get(message_id) !== undefined) {
-            process_submessages({message_id, $row: list.get_row(message_id)});
+        const $row = list?.get_row(message_id);
+        if ($row && $row.length !== 0) {
+            process_submessages({message_id, $row});
         }
     }
 }