diff --git a/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl b/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl
index 942f5a5f80..bb1afc876f 100644
--- a/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl
+++ b/Userland/Libraries/LibWeb/DOM/ShadowRoot.idl
@@ -8,6 +8,8 @@ interface ShadowRoot : DocumentFragment {
     readonly attribute ShadowRootMode mode;
     readonly attribute boolean delegatesFocus;
     readonly attribute SlotAssignmentMode slotAssignment;
+    readonly attribute boolean clonable;
+    readonly attribute boolean serializable;
     readonly attribute Element host;
     attribute EventHandler onslotchange;
 };