diff --git a/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp b/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp
index 14aedd50f3..869401c5c8 100644
--- a/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp
+++ b/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.cpp
@@ -21,9 +21,9 @@
 
 namespace Web::DOMParsing {
 
-JS::NonnullGCPtr<XMLSerializer> XMLSerializer::construct_impl(JS::Realm& realm)
+WebIDL::ExceptionOr<JS::NonnullGCPtr<XMLSerializer>> XMLSerializer::construct_impl(JS::Realm& realm)
 {
-    return (realm.heap().allocate<XMLSerializer>(realm, realm)).release_allocated_value_but_fixme_should_propagate_errors();
+    return MUST_OR_THROW_OOM(realm.heap().allocate<XMLSerializer>(realm, realm));
 }
 
 XMLSerializer::XMLSerializer(JS::Realm& realm)
diff --git a/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.h b/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.h
index e616d5a6c9..2f82d0d073 100644
--- a/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.h
+++ b/Userland/Libraries/LibWeb/DOMParsing/XMLSerializer.h
@@ -14,7 +14,7 @@ class XMLSerializer final : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(XMLSerializer, Bindings::PlatformObject);
 
 public:
-    static JS::NonnullGCPtr<XMLSerializer> construct_impl(JS::Realm&);
+    static WebIDL::ExceptionOr<JS::NonnullGCPtr<XMLSerializer>> construct_impl(JS::Realm&);
 
     virtual ~XMLSerializer() override;