diff --git a/package.json b/package.json
index cf58855..f59fe8d 100644
--- a/package.json
+++ b/package.json
@@ -30,7 +30,7 @@
   "devDependencies": {
     "@happy-dom/global-registrator": "20.0.11",
     "@types/bun": "^1.3.5",
-    "happy-dom": "20.3.4",
+    "happy-dom": "20.3.9",
     "typescript": "5.9.3"
   }
 }
\ No newline at end of file