1 files changed, 5 insertions, 0 deletions
diff --git a/js/src/vm/Interpreter.cpp b/js/src/vm/Interpreter.cpp
index 3cf9b57f6..b87d12924 100644
--- a/js/src/vm/Interpreter.cpp
+++ b/js/src/vm/Interpreter.cpp
@@ -5016,6 +5016,11 @@ js::NewObjectOperationWithTemplate(JSContext* cx, HandleObject templateObject)
 
     NewObjectKind newKind = templateObject->group()->shouldPreTenure() ? TenuredObject : GenericObject;
 
+    if (templateObject->group()->maybeUnboxedLayout()) {
+        RootedObjectGroup group(cx, templateObject->group());
+        return UnboxedPlainObject::create(cx, group, newKind);
+    }
+
     JSObject* obj = CopyInitializerObject(cx, templateObject.as<PlainObject>(), newKind);
     if (!obj)
         return nullptr;