diff --git a/src/sandbox/patchers/windowListener.ts b/src/sandbox/patchers/windowListener.ts
index e09b49d8b..fa578e2bc 100644
--- a/src/sandbox/patchers/windowListener.ts
+++ b/src/sandbox/patchers/windowListener.ts
@@ -69,8 +69,7 @@ const addCacheListener = (
   }
 
   const cacheListener = { listener, options, rawListener };
-  cachedTypeListeners.push(cacheListener);
-  listenerMap.set(type, cachedTypeListeners);
+  listenerMap.set(type, [...cachedTypeListeners, cacheListener]);
   return cacheListener;
 };