diff --git a/Userland/Applications/Spreadsheet/JSIntegration.cpp b/Userland/Applications/Spreadsheet/JSIntegration.cpp
index ea67307c78..8ee5666643 100644
--- a/Userland/Applications/Spreadsheet/JSIntegration.cpp
+++ b/Userland/Applications/Spreadsheet/JSIntegration.cpp
@@ -109,7 +109,7 @@ JS::ThrowCompletionOr<bool> SheetGlobalObject::internal_has_property(JS::Propert
     return Object::internal_has_property(name);
 }
 
-JS::ThrowCompletionOr<JS::Value> SheetGlobalObject::internal_get(const JS::PropertyKey& property_name, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> SheetGlobalObject::internal_get(const JS::PropertyKey& property_name, JS::Value receiver, JS::CacheablePropertyMetadata*) const
 {
     if (property_name.is_string()) {
         if (property_name.as_string() == "value") {
diff --git a/Userland/Applications/Spreadsheet/JSIntegration.h b/Userland/Applications/Spreadsheet/JSIntegration.h
index 93a766a11a..ac529b77e2 100644
--- a/Userland/Applications/Spreadsheet/JSIntegration.h
+++ b/Userland/Applications/Spreadsheet/JSIntegration.h
@@ -28,7 +28,7 @@ public:
     virtual ~SheetGlobalObject() override = default;
 
     virtual JS::ThrowCompletionOr<bool> internal_has_property(JS::PropertyKey const& name) const override;
-    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver, JS::CacheablePropertyMetadata*) const override;
     virtual JS::ThrowCompletionOr<bool> internal_set(JS::PropertyKey const&, JS::Value value, JS::Value receiver) override;
 
     JS_DECLARE_NATIVE_FUNCTION(get_real_cell_contents);
diff --git a/Userland/Libraries/LibJS/Runtime/ArgumentsObject.cpp b/Userland/Libraries/LibJS/Runtime/ArgumentsObject.cpp
index 3d66852ae9..97d23095b0 100644
--- a/Userland/Libraries/LibJS/Runtime/ArgumentsObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/ArgumentsObject.cpp
@@ -33,7 +33,7 @@ void ArgumentsObject::visit_edges(Cell::Visitor& visitor)
 }
 
 // 10.4.4.3 [[Get]] ( P, Receiver ), https://tc39.es/ecma262/#sec-arguments-exotic-objects-get-p-receiver
-ThrowCompletionOr<Value> ArgumentsObject::internal_get(PropertyKey const& property_key, Value receiver) const
+ThrowCompletionOr<Value> ArgumentsObject::internal_get(PropertyKey const& property_key, Value receiver, CacheablePropertyMetadata* cacheable_metadata) const
 {
     // 1. Let map be args.[[ParameterMap]].
     auto& map = *m_parameter_map;
@@ -44,7 +44,7 @@ ThrowCompletionOr<Value> ArgumentsObject::internal_get(PropertyKey const& proper
     // 3. If isMapped is false, then
     if (!is_mapped) {
         // a. Return ? OrdinaryGet(args, P, Receiver).
-        return Object::internal_get(property_key, receiver);
+        return Object::internal_get(property_key, receiver, cacheable_metadata);
     }
 
     // FIXME: a. Assert: map contains a formal parameter mapping for P.
diff --git a/Userland/Libraries/LibJS/Runtime/ArgumentsObject.h b/Userland/Libraries/LibJS/Runtime/ArgumentsObject.h
index d0e52c34b7..adcb4ff2de 100644
--- a/Userland/Libraries/LibJS/Runtime/ArgumentsObject.h
+++ b/Userland/Libraries/LibJS/Runtime/ArgumentsObject.h
@@ -23,7 +23,7 @@ public:
 
     virtual ThrowCompletionOr<Optional<PropertyDescriptor>> internal_get_own_property(PropertyKey const&) const override;
     virtual ThrowCompletionOr<bool> internal_define_own_property(PropertyKey const&, PropertyDescriptor const&) override;
-    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver) const override;
+    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver, CacheablePropertyMetadata*) const override;
     virtual ThrowCompletionOr<bool> internal_set(PropertyKey const&, Value value, Value receiver) override;
     virtual ThrowCompletionOr<bool> internal_delete(PropertyKey const&) override;
 
diff --git a/Userland/Libraries/LibJS/Runtime/IndexedProperties.h b/Userland/Libraries/LibJS/Runtime/IndexedProperties.h
index 4532d01a54..b0a923a85e 100644
--- a/Userland/Libraries/LibJS/Runtime/IndexedProperties.h
+++ b/Userland/Libraries/LibJS/Runtime/IndexedProperties.h
@@ -15,6 +15,8 @@ namespace JS {
 struct ValueAndAttributes {
     Value value;
     PropertyAttributes attributes { default_attributes };
+
+    Optional<u32> property_offset {};
 };
 
 class IndexedProperties;
diff --git a/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.cpp b/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.cpp
index 55e89eb7ad..5917d9bba8 100644
--- a/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.cpp
@@ -137,14 +137,14 @@ ThrowCompletionOr<bool> ModuleNamespaceObject::internal_has_property(PropertyKey
 }
 
 // 10.4.6.8 [[Get]] ( P, Receiver ), https://tc39.es/ecma262/#sec-module-namespace-exotic-objects-get-p-receiver
-ThrowCompletionOr<Value> ModuleNamespaceObject::internal_get(PropertyKey const& property_key, Value receiver) const
+ThrowCompletionOr<Value> ModuleNamespaceObject::internal_get(PropertyKey const& property_key, Value receiver, CacheablePropertyMetadata* cacheable_metadata) const
 {
     auto& vm = this->vm();
 
     // 1. If Type(P) is Symbol, then
     if (property_key.is_symbol()) {
         // a. Return ! OrdinaryGet(O, P, Receiver).
-        return MUST(Object::internal_get(property_key, receiver));
+        return MUST(Object::internal_get(property_key, receiver, cacheable_metadata));
     }
 
     // 2. Let exports be O.[[Exports]].
diff --git a/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.h b/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.h
index a592894dc0..d6dd3bce04 100644
--- a/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.h
+++ b/Userland/Libraries/LibJS/Runtime/ModuleNamespaceObject.h
@@ -25,7 +25,7 @@ public:
     virtual ThrowCompletionOr<Optional<PropertyDescriptor>> internal_get_own_property(PropertyKey const&) const override;
     virtual ThrowCompletionOr<bool> internal_define_own_property(PropertyKey const&, PropertyDescriptor const&) override;
     virtual ThrowCompletionOr<bool> internal_has_property(PropertyKey const&) const override;
-    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver) const override;
+    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver, CacheablePropertyMetadata* = nullptr) const override;
     virtual ThrowCompletionOr<bool> internal_set(PropertyKey const&, Value value, Value receiver) override;
     virtual ThrowCompletionOr<bool> internal_delete(PropertyKey const&) override;
     virtual ThrowCompletionOr<MarkedVector<Value>> internal_own_property_keys() const override;
diff --git a/Userland/Libraries/LibJS/Runtime/Object.cpp b/Userland/Libraries/LibJS/Runtime/Object.cpp
index 7da195839d..a0fdd8481d 100644
--- a/Userland/Libraries/LibJS/Runtime/Object.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Object.cpp
@@ -764,7 +764,7 @@ ThrowCompletionOr<Optional<PropertyDescriptor>> Object::internal_get_own_propert
     PropertyDescriptor descriptor;
 
     // 3. Let X be O's own property whose key is P.
-    auto [value, attributes] = *maybe_storage_entry;
+    auto [value, attributes, property_offset] = *maybe_storage_entry;
 
     // 4. If X is a data property, then
     if (!value.is_accessor()) {
@@ -791,6 +791,9 @@ ThrowCompletionOr<Optional<PropertyDescriptor>> Object::internal_get_own_propert
     // 7. Set D.[[Configurable]] to the value of X's [[Configurable]] attribute.
     descriptor.configurable = attributes.is_configurable();
 
+    // Non-standard: Add the property offset to the descriptor. This is used to populate CacheablePropertyMetadata.
+    descriptor.property_offset = property_offset;
+
     // 8. Return D.
     return descriptor;
 }
@@ -836,7 +839,7 @@ ThrowCompletionOr<bool> Object::internal_has_property(PropertyKey const& propert
 }
 
 // 10.1.8 [[Get]] ( P, Receiver ), https://tc39.es/ecma262/#sec-ordinary-object-internal-methods-and-internal-slots-get-p-receiver
-ThrowCompletionOr<Value> Object::internal_get(PropertyKey const& property_key, Value receiver) const
+ThrowCompletionOr<Value> Object::internal_get(PropertyKey const& property_key, Value receiver, CacheablePropertyMetadata* cacheable_metadata) const
 {
     VERIFY(!receiver.is_empty());
     VERIFY(property_key.is_valid());
@@ -860,8 +863,16 @@ ThrowCompletionOr<Value> Object::internal_get(PropertyKey const& property_key, V
     }
 
     // 3. If IsDataDescriptor(desc) is true, return desc.[[Value]].
-    if (descriptor->is_data_descriptor())
+    if (descriptor->is_data_descriptor()) {
+        // Non-standard: If the caller has requested cacheable metadata and the property is an own property, fill it in.
+        if (cacheable_metadata && descriptor->property_offset.has_value()) {
+            *cacheable_metadata = CacheablePropertyMetadata {
+                .type = CacheablePropertyMetadata::Type::OwnProperty,
+                .property_offset = descriptor->property_offset.value(),
+            };
+        }
         return *descriptor->value;
+    }
 
     // 4. Assert: IsAccessorDescriptor(desc) is true.
     VERIFY(descriptor->is_accessor_descriptor());
@@ -1075,6 +1086,7 @@ Optional<ValueAndAttributes> Object::storage_get(PropertyKey const& property_key
 
     Value value;
     PropertyAttributes attributes;
+    Optional<u32> property_offset;
 
     if (property_key.is_number()) {
         auto value_and_attributes = m_indexed_properties.get(property_key.as_number());
@@ -1094,9 +1106,10 @@ Optional<ValueAndAttributes> Object::storage_get(PropertyKey const& property_key
 
         value = m_storage[metadata->offset];
         attributes = metadata->attributes;
+        property_offset = metadata->offset;
     }
 
-    return ValueAndAttributes { .value = value, .attributes = attributes };
+    return ValueAndAttributes { .value = value, .attributes = attributes, .property_offset = property_offset };
 }
 
 bool Object::storage_has(PropertyKey const& property_key) const
@@ -1111,7 +1124,7 @@ void Object::storage_set(PropertyKey const& property_key, ValueAndAttributes con
 {
     VERIFY(property_key.is_valid());
 
-    auto [value, attributes] = value_and_attributes;
+    auto [value, attributes, _] = value_and_attributes;
 
     if (property_key.is_number()) {
         auto index = property_key.as_number();
diff --git a/Userland/Libraries/LibJS/Runtime/Object.h b/Userland/Libraries/LibJS/Runtime/Object.h
index bde5890b5c..7f2b041291 100644
--- a/Userland/Libraries/LibJS/Runtime/Object.h
+++ b/Userland/Libraries/LibJS/Runtime/Object.h
@@ -39,6 +39,17 @@ struct PrivateElement {
     Handle<Value> value;
 };
 
+// Non-standard: This is information optionally returned by object property access functions.
+//               It can be used to implement inline caches for property lookup.
+struct CacheablePropertyMetadata {
+    enum class Type {
+        NotCacheable,
+        OwnProperty,
+    };
+    Type type { Type::NotCacheable };
+    Optional<u32> property_offset;
+};
+
 class Object : public Cell {
     JS_CELL(Object, Cell);
 
@@ -118,7 +129,7 @@ public:
     virtual ThrowCompletionOr<Optional<PropertyDescriptor>> internal_get_own_property(PropertyKey const&) const;
     virtual ThrowCompletionOr<bool> internal_define_own_property(PropertyKey const&, PropertyDescriptor const&);
     virtual ThrowCompletionOr<bool> internal_has_property(PropertyKey const&) const;
-    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver) const;
+    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver, CacheablePropertyMetadata* = nullptr) const;
     virtual ThrowCompletionOr<bool> internal_set(PropertyKey const&, Value value, Value receiver);
     virtual ThrowCompletionOr<bool> internal_delete(PropertyKey const&);
     virtual ThrowCompletionOr<MarkedVector<Value>> internal_own_property_keys() const;
diff --git a/Userland/Libraries/LibJS/Runtime/PropertyDescriptor.h b/Userland/Libraries/LibJS/Runtime/PropertyDescriptor.h
index 3fc549d9c5..a3cc985eb9 100644
--- a/Userland/Libraries/LibJS/Runtime/PropertyDescriptor.h
+++ b/Userland/Libraries/LibJS/Runtime/PropertyDescriptor.h
@@ -40,6 +40,8 @@ public:
     Optional<bool> writable {};
     Optional<bool> enumerable {};
     Optional<bool> configurable {};
+
+    Optional<u32> property_offset {};
 };
 
 }
diff --git a/Userland/Libraries/LibJS/Runtime/ProxyObject.cpp b/Userland/Libraries/LibJS/Runtime/ProxyObject.cpp
index f23d0a852c..1f4b232f8d 100644
--- a/Userland/Libraries/LibJS/Runtime/ProxyObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/ProxyObject.cpp
@@ -452,8 +452,10 @@ ThrowCompletionOr<bool> ProxyObject::internal_has_property(PropertyKey const& pr
 }
 
 // 10.5.8 [[Get]] ( P, Receiver ), https://tc39.es/ecma262/#sec-proxy-object-internal-methods-and-internal-slots-get-p-receiver
-ThrowCompletionOr<Value> ProxyObject::internal_get(PropertyKey const& property_key, Value receiver) const
+ThrowCompletionOr<Value> ProxyObject::internal_get(PropertyKey const& property_key, Value receiver, CacheablePropertyMetadata*) const
 {
+    // NOTE: We don't return any cacheable metadata for proxy lookups.
+
     VERIFY(!receiver.is_empty());
 
     auto& vm = this->vm();
diff --git a/Userland/Libraries/LibJS/Runtime/ProxyObject.h b/Userland/Libraries/LibJS/Runtime/ProxyObject.h
index 15eec64a70..15fe721904 100644
--- a/Userland/Libraries/LibJS/Runtime/ProxyObject.h
+++ b/Userland/Libraries/LibJS/Runtime/ProxyObject.h
@@ -38,7 +38,7 @@ public:
     virtual ThrowCompletionOr<Optional<PropertyDescriptor>> internal_get_own_property(PropertyKey const&) const override;
     virtual ThrowCompletionOr<bool> internal_define_own_property(PropertyKey const&, PropertyDescriptor const&) override;
     virtual ThrowCompletionOr<bool> internal_has_property(PropertyKey const&) const override;
-    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver) const override;
+    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const&, Value receiver, CacheablePropertyMetadata*) const override;
     virtual ThrowCompletionOr<bool> internal_set(PropertyKey const&, Value value, Value receiver) override;
     virtual ThrowCompletionOr<bool> internal_delete(PropertyKey const&) override;
     virtual ThrowCompletionOr<MarkedVector<Value>> internal_own_property_keys() const override;
diff --git a/Userland/Libraries/LibJS/Runtime/TypedArray.h b/Userland/Libraries/LibJS/Runtime/TypedArray.h
index f925ad72ca..4a81ea75a7 100644
--- a/Userland/Libraries/LibJS/Runtime/TypedArray.h
+++ b/Userland/Libraries/LibJS/Runtime/TypedArray.h
@@ -288,7 +288,7 @@ public:
     }
 
     // 10.4.5.4 [[Get]] ( P, Receiver ), 10.4.5.4 [[Get]] ( P, Receiver )
-    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const& property_key, Value receiver) const override
+    virtual ThrowCompletionOr<Value> internal_get(PropertyKey const& property_key, Value receiver, CacheablePropertyMetadata* cacheable_metadata) const override
     {
         VERIFY(!receiver.is_empty());
 
@@ -310,7 +310,7 @@ public:
         }
 
         // 2. Return ? OrdinaryGet(O, P, Receiver).
-        return Object::internal_get(property_key, receiver);
+        return Object::internal_get(property_key, receiver, cacheable_metadata);
     }
 
     // 10.4.5.5 [[Set]] ( P, V, Receiver ), https://tc39.es/ecma262/#sec-integer-indexed-exotic-objects-set-p-v-receiver
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp
index 4767b2ded8..de19d3554d 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp
@@ -396,13 +396,13 @@ JS::ThrowCompletionOr<bool> CSSStyleDeclaration::internal_has_property(JS::Prope
     return property_id_from_name(name.to_string()) != CSS::PropertyID::Invalid;
 }
 
-JS::ThrowCompletionOr<JS::Value> CSSStyleDeclaration::internal_get(JS::PropertyKey const& name, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> CSSStyleDeclaration::internal_get(JS::PropertyKey const& name, JS::Value receiver, JS::CacheablePropertyMetadata* cacheable_metadata) const
 {
     if (!name.is_string())
-        return Base::internal_get(name, receiver);
+        return Base::internal_get(name, receiver, cacheable_metadata);
     auto property_id = property_id_from_name(name.to_string());
     if (property_id == CSS::PropertyID::Invalid)
-        return Base::internal_get(name, receiver);
+        return Base::internal_get(name, receiver, cacheable_metadata);
     if (auto maybe_property = property(property_id); maybe_property.has_value())
         return { JS::PrimitiveString::create(vm(), maybe_property->value->to_string().release_value_but_fixme_should_propagate_errors().to_deprecated_string()) };
     return { JS::PrimitiveString::create(vm(), String {}) };
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h
index 139994eaf2..62cabc1a4d 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h
@@ -41,7 +41,7 @@ public:
     virtual DeprecatedString serialized() const = 0;
 
     virtual JS::ThrowCompletionOr<bool> internal_has_property(JS::PropertyKey const& name) const override;
-    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver, JS::CacheablePropertyMetadata*) const override;
     virtual JS::ThrowCompletionOr<bool> internal_set(JS::PropertyKey const&, JS::Value value, JS::Value receiver) override;
 
 protected:
diff --git a/Userland/Libraries/LibWeb/HTML/Location.cpp b/Userland/Libraries/LibWeb/HTML/Location.cpp
index afcd037982..f4fd9fa132 100644
--- a/Userland/Libraries/LibWeb/HTML/Location.cpp
+++ b/Userland/Libraries/LibWeb/HTML/Location.cpp
@@ -442,13 +442,13 @@ JS::ThrowCompletionOr<bool> Location::internal_define_own_property(JS::PropertyK
 }
 
 // 7.10.5.7 [[Get]] ( P, Receiver ), https://html.spec.whatwg.org/multipage/history.html#location-get
-JS::ThrowCompletionOr<JS::Value> Location::internal_get(JS::PropertyKey const& property_key, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> Location::internal_get(JS::PropertyKey const& property_key, JS::Value receiver, JS::CacheablePropertyMetadata* cacheable_metadata) const
 {
     auto& vm = this->vm();
 
     // 1. If IsPlatformObjectSameOrigin(this) is true, then return ? OrdinaryGet(this, P, Receiver).
     if (HTML::is_platform_object_same_origin(*this))
-        return JS::Object::internal_get(property_key, receiver);
+        return JS::Object::internal_get(property_key, receiver, cacheable_metadata);
 
     // 2. Return ? CrossOriginGet(this, P, Receiver).
     return HTML::cross_origin_get(vm, static_cast<JS::Object const&>(*this), property_key, receiver);
diff --git a/Userland/Libraries/LibWeb/HTML/Location.h b/Userland/Libraries/LibWeb/HTML/Location.h
index e154137562..b7c4b0449d 100644
--- a/Userland/Libraries/LibWeb/HTML/Location.h
+++ b/Userland/Libraries/LibWeb/HTML/Location.h
@@ -58,7 +58,7 @@ public:
     virtual JS::ThrowCompletionOr<bool> internal_prevent_extensions() override;
     virtual JS::ThrowCompletionOr<Optional<JS::PropertyDescriptor>> internal_get_own_property(JS::PropertyKey const&) const override;
     virtual JS::ThrowCompletionOr<bool> internal_define_own_property(JS::PropertyKey const&, JS::PropertyDescriptor const&) override;
-    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver, JS::CacheablePropertyMetadata*) const override;
     virtual JS::ThrowCompletionOr<bool> internal_set(JS::PropertyKey const&, JS::Value value, JS::Value receiver) override;
     virtual JS::ThrowCompletionOr<bool> internal_delete(JS::PropertyKey const&) override;
     virtual JS::ThrowCompletionOr<JS::MarkedVector<JS::Value>> internal_own_property_keys() const override;
diff --git a/Userland/Libraries/LibWeb/HTML/WindowProxy.cpp b/Userland/Libraries/LibWeb/HTML/WindowProxy.cpp
index fdcf39d01a..7cf010ece5 100644
--- a/Userland/Libraries/LibWeb/HTML/WindowProxy.cpp
+++ b/Userland/Libraries/LibWeb/HTML/WindowProxy.cpp
@@ -144,7 +144,7 @@ JS::ThrowCompletionOr<bool> WindowProxy::internal_define_own_property(JS::Proper
 }
 
 // 7.4.7 [[Get]] ( P, Receiver ), https://html.spec.whatwg.org/multipage/window-object.html#windowproxy-get
-JS::ThrowCompletionOr<JS::Value> WindowProxy::internal_get(JS::PropertyKey const& property_key, JS::Value receiver) const
+JS::ThrowCompletionOr<JS::Value> WindowProxy::internal_get(JS::PropertyKey const& property_key, JS::Value receiver, JS::CacheablePropertyMetadata* cacheable_metadata) const
 {
     auto& vm = this->vm();
 
@@ -156,7 +156,7 @@ JS::ThrowCompletionOr<JS::Value> WindowProxy::internal_get(JS::PropertyKey const
     // 3. If IsPlatformObjectSameOrigin(W) is true, then return ? OrdinaryGet(this, P, Receiver).
     // NOTE: this is passed rather than W as OrdinaryGet and CrossOriginGet will invoke the [[GetOwnProperty]] internal method.
     if (is_platform_object_same_origin(*m_window))
-        return JS::Object::internal_get(property_key, receiver);
+        return JS::Object::internal_get(property_key, receiver, cacheable_metadata);
 
     // 4. Return ? CrossOriginGet(this, P, Receiver).
     // NOTE: this is passed rather than W as OrdinaryGet and CrossOriginGet will invoke the [[GetOwnProperty]] internal method.
diff --git a/Userland/Libraries/LibWeb/HTML/WindowProxy.h b/Userland/Libraries/LibWeb/HTML/WindowProxy.h
index 5c32c7b63e..43dd46e0a1 100644
--- a/Userland/Libraries/LibWeb/HTML/WindowProxy.h
+++ b/Userland/Libraries/LibWeb/HTML/WindowProxy.h
@@ -26,7 +26,7 @@ public:
     virtual JS::ThrowCompletionOr<bool> internal_prevent_extensions() override;
     virtual JS::ThrowCompletionOr<Optional<JS::PropertyDescriptor>> internal_get_own_property(JS::PropertyKey const&) const override;
     virtual JS::ThrowCompletionOr<bool> internal_define_own_property(JS::PropertyKey const&, JS::PropertyDescriptor const&) override;
-    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver) const override;
+    virtual JS::ThrowCompletionOr<JS::Value> internal_get(JS::PropertyKey const&, JS::Value receiver, JS::CacheablePropertyMetadata*) const override;
     virtual JS::ThrowCompletionOr<bool> internal_set(JS::PropertyKey const&, JS::Value value, JS::Value receiver) override;
     virtual JS::ThrowCompletionOr<bool> internal_delete(JS::PropertyKey const&) override;
     virtual JS::ThrowCompletionOr<JS::MarkedVector<JS::Value>> internal_own_property_keys() const override;