diff --git a/comfy_api/feature_flags.py b/comfy_api/feature_flags.py
index 0d4389a6e..bfb77eb5f 100644
--- a/comfy_api/feature_flags.py
+++ b/comfy_api/feature_flags.py
@@ -13,6 +13,7 @@ from comfy.cli_args import args
 SERVER_FEATURE_FLAGS: Dict[str, Any] = {
     "supports_preview_metadata": True,
     "max_upload_size": args.max_upload_size * 1024 * 1024, # Convert MB to bytes
+    "extension": {"manager": {"supports_v4": True}},
 }