diff --git a/Userland/Libraries/LibJS/Runtime/AbstractOperations.cpp b/Userland/Libraries/LibJS/Runtime/AbstractOperations.cpp
index 65d840a152..c3d12c3855 100644
--- a/Userland/Libraries/LibJS/Runtime/AbstractOperations.cpp
+++ b/Userland/Libraries/LibJS/Runtime/AbstractOperations.cpp
@@ -87,6 +87,10 @@ ThrowCompletionOr<NonnullGCPtr<Object>> construct_impl(VM&, FunctionObject& func
 // 7.3.19 LengthOfArrayLike ( obj ), https://tc39.es/ecma262/#sec-lengthofarraylike
 ThrowCompletionOr<size_t> length_of_array_like(VM& vm, Object const& object)
 {
+    // OPTIMIZATION: For Array objects with a magical "length" property, it should always reflect the size of indexed property storage.
+    if (object.has_magical_length_property())
+        return object.indexed_properties().array_like_size();
+
     // 1. Return ℝ(? ToLength(? Get(obj, "length"))).
     return TRY(object.get(vm.names.length)).to_length(vm);
 }
diff --git a/Userland/Libraries/LibJS/Runtime/Object.h b/Userland/Libraries/LibJS/Runtime/Object.h
index 9b8de50445..d92ae61f4a 100644
--- a/Userland/Libraries/LibJS/Runtime/Object.h
+++ b/Userland/Libraries/LibJS/Runtime/Object.h
@@ -224,6 +224,7 @@ public:
     static FlatPtr may_interfere_with_indexed_property_access_offset() { return OFFSET_OF(Object, m_may_interfere_with_indexed_property_access); }
     static FlatPtr indexed_properties_offset() { return OFFSET_OF(Object, m_indexed_properties); }
 
+    [[nodiscard]] bool has_magical_length_property() const { return m_has_magical_length_property; }
     static FlatPtr has_magical_length_property_offset() { return OFFSET_OF(Object, m_has_magical_length_property); }
 
     [[nodiscard]] bool is_typed_array() const { return m_is_typed_array; }