LibWeb: Make CSSStyleDeclaration GC-allocated

18 files changed, 146 insertions, 129 deletions

diff --git a/Userland/Libraries/LibWeb/Bindings/CSSStyleDeclarationWrapperCustom.cpp b/Userland/Libraries/LibWeb/Bindings/CSSStyleDeclarationWrapperCustom.cpp
deleted file mode 100644
index 0f7eef1aae..0000000000
--- a/Userland/Libraries/LibWeb/Bindings/CSSStyleDeclarationWrapperCustom.cpp
+++ /dev/null
@@ -1,62 +0,0 @@
-/*
- * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#include <LibJS/Runtime/Completion.h>
-#include <LibWeb/Bindings/CSSStyleDeclarationWrapper.h>
-#include <LibWeb/DOM/Element.h>
-
-namespace Web::Bindings {
-
-static CSS::PropertyID property_id_from_name(StringView name)
-{
-    // FIXME: Perhaps this should go in the code generator.
-    if (name == "cssFloat"sv)
-        return CSS::PropertyID::Float;
-
-    if (auto property_id = CSS::property_id_from_camel_case_string(name); property_id != CSS::PropertyID::Invalid)
-        return property_id;
-
-    if (auto property_id = CSS::property_id_from_string(name); property_id != CSS::PropertyID::Invalid)
-        return property_id;
-
-    return CSS::PropertyID::Invalid;
-}
-
-JS::ThrowCompletionOr<bool> CSSStyleDeclarationWrapper::internal_has_property(JS::PropertyKey const& name) const
-{
-    if (!name.is_string())
-        return Base::internal_has_property(name);
-    return property_id_from_name(name.to_string()) != CSS::PropertyID::Invalid;
-}
-
-JS::ThrowCompletionOr<JS::Value> CSSStyleDeclarationWrapper::internal_get(JS::PropertyKey const& name, JS::Value receiver) const
-{
-    if (!name.is_string())
-        return Base::internal_get(name, receiver);
-    auto property_id = property_id_from_name(name.to_string());
-    if (property_id == CSS::PropertyID::Invalid)
-        return Base::internal_get(name, receiver);
-    if (auto maybe_property = impl().property(property_id); maybe_property.has_value())
-        return { js_string(vm(), maybe_property->value->to_string()) };
-    return { js_string(vm(), String::empty()) };
-}
-
-JS::ThrowCompletionOr<bool> CSSStyleDeclarationWrapper::internal_set(JS::PropertyKey const& name, JS::Value value, JS::Value receiver)
-{
-    if (!name.is_string())
-        return Base::internal_set(name, value, receiver);
-    auto& vm = this->vm();
-    auto property_id = property_id_from_name(name.to_string());
-    if (property_id == CSS::PropertyID::Invalid)
-        return Base::internal_set(name, value, receiver);
-
-    auto css_text = TRY(value.to_string(vm));
-
-    impl().set_property(property_id, css_text);
-    return true;
-}
-
-}
diff --git a/Userland/Libraries/LibWeb/Bindings/WindowObject.cpp b/Userland/Libraries/LibWeb/Bindings/WindowObject.cpp
index 3ac4ff6ba7..32624314d2 100644
--- a/Userland/Libraries/LibWeb/Bindings/WindowObject.cpp
+++ b/Userland/Libraries/LibWeb/Bindings/WindowObject.cpp
@@ -14,7 +14,6 @@
 #include <LibJS/Runtime/Shape.h>
 #include <LibTextCodec/Decoder.h>
 #include <LibWeb/Bindings/CSSNamespace.h>
-#include <LibWeb/Bindings/CSSStyleDeclarationWrapper.h>
 #include <LibWeb/Bindings/CryptoWrapper.h>
 #include <LibWeb/Bindings/DocumentWrapper.h>
 #include <LibWeb/Bindings/ElementWrapper.h>
@@ -526,7 +525,7 @@ JS_DEFINE_NATIVE_FUNCTION(WindowObject::get_computed_style)
     if (!is<ElementWrapper>(object))
         return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "DOM element");
 
-    return wrap(realm, impl->get_computed_style(static_cast<ElementWrapper*>(object)->impl()));
+    return wrap(realm, *impl->get_computed_style(static_cast<ElementWrapper*>(object)->impl()));
 }
 
 JS_DEFINE_NATIVE_FUNCTION(WindowObject::get_selection)
diff --git a/Userland/Libraries/LibWeb/CMakeLists.txt b/Userland/Libraries/LibWeb/CMakeLists.txt
index 65e039f404..cb794c1f3d 100644
--- a/Userland/Libraries/LibWeb/CMakeLists.txt
+++ b/Userland/Libraries/LibWeb/CMakeLists.txt
@@ -4,7 +4,6 @@ set(SOURCES
     Bindings/AudioConstructor.cpp
     Bindings/CrossOriginAbstractOperations.cpp
     Bindings/CSSNamespace.cpp
-    Bindings/CSSStyleDeclarationWrapperCustom.cpp
     Bindings/EventListenerWrapper.cpp
     Bindings/EventTargetWrapperFactory.cpp
     Bindings/EventWrapperFactory.cpp
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp
index 853c471fa8..e5b4644463 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.cpp
@@ -1,17 +1,31 @@
 /*
- * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2018-2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSStyleDeclarationPrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSStyleDeclaration.h>
 #include <LibWeb/CSS/Parser/Parser.h>
+#include <LibWeb/DOM/Document.h>
 #include <LibWeb/DOM/Element.h>
 
 namespace Web::CSS {
 
-PropertyOwningCSSStyleDeclaration::PropertyOwningCSSStyleDeclaration(Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties)
-    : m_properties(move(properties))
+CSSStyleDeclaration::CSSStyleDeclaration(Bindings::WindowObject& window_object)
+    : PlatformObject(window_object.ensure_web_prototype<Bindings::CSSStyleDeclarationPrototype>("CSSStyleDeclaration"))
+{
+}
+
+PropertyOwningCSSStyleDeclaration* PropertyOwningCSSStyleDeclaration::create(Bindings::WindowObject& window_object, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties)
+{
+    return window_object.heap().allocate<PropertyOwningCSSStyleDeclaration>(window_object.realm(), window_object, move(properties), move(custom_properties));
+}
+
+PropertyOwningCSSStyleDeclaration::PropertyOwningCSSStyleDeclaration(Bindings::WindowObject& window_object, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties)
+    : CSSStyleDeclaration(window_object)
+    , m_properties(move(properties))
     , m_custom_properties(move(custom_properties))
 {
 }
@@ -23,8 +37,14 @@ String PropertyOwningCSSStyleDeclaration::item(size_t index) const
     return CSS::string_from_property_id(m_properties[index].property_id);
 }
 
+ElementInlineCSSStyleDeclaration* ElementInlineCSSStyleDeclaration::create(DOM::Element& element, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties)
+{
+    auto& window_object = element.document().preferred_window_object();
+    return window_object.heap().allocate<ElementInlineCSSStyleDeclaration>(window_object.realm(), element, move(properties), move(custom_properties));
+}
+
 ElementInlineCSSStyleDeclaration::ElementInlineCSSStyleDeclaration(DOM::Element& element, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties)
-    : PropertyOwningCSSStyleDeclaration(move(properties), move(custom_properties))
+    : PropertyOwningCSSStyleDeclaration(element.document().preferred_window_object(), move(properties), move(custom_properties))
     , m_element(element.make_weak_ptr<DOM::Element>())
 {
 }
@@ -284,4 +304,52 @@ String PropertyOwningCSSStyleDeclaration::serialized() const
     return builder.to_string();
 }
 
+static CSS::PropertyID property_id_from_name(StringView name)
+{
+    // FIXME: Perhaps this should go in the code generator.
+    if (name == "cssFloat"sv)
+        return CSS::PropertyID::Float;
+
+    if (auto property_id = CSS::property_id_from_camel_case_string(name); property_id != CSS::PropertyID::Invalid)
+        return property_id;
+
+    if (auto property_id = CSS::property_id_from_string(name); property_id != CSS::PropertyID::Invalid)
+        return property_id;
+
+    return CSS::PropertyID::Invalid;
+}
+
+JS::ThrowCompletionOr<bool> CSSStyleDeclaration::internal_has_property(JS::PropertyKey const& name) const
+{
+    if (!name.is_string())
+        return Base::internal_has_property(name);
+    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
+{
+    if (!name.is_string())
+        return Base::internal_get(name, receiver);
+    auto property_id = property_id_from_name(name.to_string());
+    if (property_id == CSS::PropertyID::Invalid)
+        return Base::internal_get(name, receiver);
+    if (auto maybe_property = property(property_id); maybe_property.has_value())
+        return { js_string(vm(), maybe_property->value->to_string()) };
+    return { js_string(vm(), String::empty()) };
+}
+
+JS::ThrowCompletionOr<bool> CSSStyleDeclaration::internal_set(JS::PropertyKey const& name, JS::Value value, JS::Value receiver)
+{
+    if (!name.is_string())
+        return Base::internal_set(name, value, receiver);
+    auto property_id = property_id_from_name(name.to_string());
+    if (property_id == CSS::PropertyID::Invalid)
+        return Base::internal_set(name, value, receiver);
+
+    auto css_text = TRY(value.to_string(vm()));
+
+    impl().set_property(property_id, css_text);
+    return true;
+}
+
 }
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h
index 4b726a4274..ac8a3e2471 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.h
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2018-2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -8,7 +8,7 @@
 
 #include <AK/String.h>
 #include <AK/Vector.h>
-#include <LibWeb/Bindings/Wrappable.h>
+#include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/CSS/StyleValue.h>
 
 namespace Web::CSS {
@@ -25,14 +25,14 @@ struct StyleProperty {
     String custom_name {};
 };
 
-class CSSStyleDeclaration
-    : public RefCounted<CSSStyleDeclaration>
-    , public Bindings::Wrappable {
-public:
-    using WrapperType = Bindings::CSSStyleDeclarationWrapper;
+class CSSStyleDeclaration : public Bindings::PlatformObject {
+    JS_OBJECT(CSSStyleDeclaration, Bindings::PlatformObject);
 
+public:
     virtual ~CSSStyleDeclaration() = default;
 
+    CSSStyleDeclaration& impl() { return *this; }
+
     virtual size_t length() const = 0;
     virtual String item(size_t index) const = 0;
 
@@ -52,18 +52,21 @@ public:
 
     virtual String 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<bool> internal_set(JS::PropertyKey const&, JS::Value value, JS::Value receiver) override;
+
 protected:
-    CSSStyleDeclaration() = default;
+    CSSStyleDeclaration(Bindings::WindowObject&);
 };
 
 class PropertyOwningCSSStyleDeclaration : public CSSStyleDeclaration {
+    JS_OBJECT(PropertyOwningCSSStyleDeclaration, CSSStyleDeclaration);
     friend class ElementInlineCSSStyleDeclaration;
 
 public:
-    static NonnullRefPtr<PropertyOwningCSSStyleDeclaration> create(Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties)
-    {
-        return adopt_ref(*new PropertyOwningCSSStyleDeclaration(move(properties), move(custom_properties)));
-    }
+    static PropertyOwningCSSStyleDeclaration* create(Bindings::WindowObject&, Vector<StyleProperty>, HashMap<String, StyleProperty> custom_properties);
+    PropertyOwningCSSStyleDeclaration(Bindings::WindowObject&, Vector<StyleProperty>, HashMap<String, StyleProperty>);
 
     virtual ~PropertyOwningCSSStyleDeclaration() override = default;
 
@@ -83,8 +86,6 @@ public:
     virtual String serialized() const final override;
 
 protected:
-    explicit PropertyOwningCSSStyleDeclaration(Vector<StyleProperty>, HashMap<String, StyleProperty>);
-
     virtual void update_style_attribute() { }
 
 private:
@@ -95,8 +96,12 @@ private:
 };
 
 class ElementInlineCSSStyleDeclaration final : public PropertyOwningCSSStyleDeclaration {
+    JS_OBJECT(ElementInlineCSSStyleDeclaration, PropertyOwningCSSStyleDeclaration);
+
 public:
-    static NonnullRefPtr<ElementInlineCSSStyleDeclaration> create(DOM::Element& element, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties) { return adopt_ref(*new ElementInlineCSSStyleDeclaration(element, move(properties), move(custom_properties))); }
+    static ElementInlineCSSStyleDeclaration* create(DOM::Element&, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties);
+    explicit ElementInlineCSSStyleDeclaration(DOM::Element&, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties);
+
     virtual ~ElementInlineCSSStyleDeclaration() override = default;
 
     DOM::Element* element() { return m_element.ptr(); }
@@ -105,8 +110,6 @@ public:
     bool is_updating() const { return m_updating; }
 
 private:
-    explicit ElementInlineCSSStyleDeclaration(DOM::Element&, Vector<StyleProperty> properties, HashMap<String, StyleProperty> custom_properties);
-
     virtual void update_style_attribute() override;
 
     WeakPtr<DOM::Element> m_element;
@@ -118,7 +121,6 @@ private:
 }
 
 namespace Web::Bindings {
-
-CSSStyleDeclarationWrapper* wrap(JS::Realm&, CSS::CSSStyleDeclaration&);
-
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSStyleDeclaration& object) { return &object; }
+using CSSStyleDeclarationWrapper = Web::CSS::CSSStyleDeclaration;
 }
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.idl b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.idl
index c94c7ac1f3..c7df224e6a 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleDeclaration.idl
@@ -1,4 +1,4 @@
-[CustomGet,CustomSet,CustomHasProperty]
+[NoInstanceWrapper]
 interface CSSStyleDeclaration {
 
     readonly attribute unsigned long length;
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp
index 25757b1636..47d829a36c 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp
@@ -11,23 +11,29 @@
 
 namespace Web::CSS {
 
-CSSStyleRule* CSSStyleRule::create(Bindings::WindowObject& window_object, NonnullRefPtrVector<Web::CSS::Selector>&& selectors, NonnullRefPtr<Web::CSS::CSSStyleDeclaration>&& declaration)
+CSSStyleRule* CSSStyleRule::create(Bindings::WindowObject& window_object, NonnullRefPtrVector<Web::CSS::Selector>&& selectors, CSSStyleDeclaration& declaration)
 {
-    return window_object.heap().allocate<CSSStyleRule>(window_object.realm(), window_object, move(selectors), move(declaration));
+    return window_object.heap().allocate<CSSStyleRule>(window_object.realm(), window_object, move(selectors), declaration);
 }
 
-CSSStyleRule::CSSStyleRule(Bindings::WindowObject& window_object, NonnullRefPtrVector<Selector>&& selectors, NonnullRefPtr<CSSStyleDeclaration>&& declaration)
+CSSStyleRule::CSSStyleRule(Bindings::WindowObject& window_object, NonnullRefPtrVector<Selector>&& selectors, CSSStyleDeclaration& declaration)
     : CSSRule(window_object)
     , m_selectors(move(selectors))
-    , m_declaration(move(declaration))
+    , m_declaration(declaration)
 {
     set_prototype(&window_object.ensure_web_prototype<Bindings::CSSStyleRulePrototype>("CSSStyleRule"));
 }
 
+void CSSStyleRule::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(&m_declaration);
+}
+
 // https://www.w3.org/TR/cssom/#dom-cssstylerule-style
 CSSStyleDeclaration* CSSStyleRule::style()
 {
-    return m_declaration;
+    return &m_declaration;
 }
 
 // https://www.w3.org/TR/cssom/#serialize-a-css-rule
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h
index cff6461137..27f2ced9cc 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h
@@ -21,8 +21,8 @@ class CSSStyleRule final : public CSSRule {
     AK_MAKE_NONMOVABLE(CSSStyleRule);
 
 public:
-    static CSSStyleRule* create(Bindings::WindowObject&, NonnullRefPtrVector<Selector>&&, NonnullRefPtr<CSSStyleDeclaration>&&);
-    CSSStyleRule(Bindings::WindowObject&, NonnullRefPtrVector<Selector>&&, NonnullRefPtr<CSSStyleDeclaration>&&);
+    static CSSStyleRule* create(Bindings::WindowObject&, NonnullRefPtrVector<Selector>&&, CSSStyleDeclaration&);
+    CSSStyleRule(Bindings::WindowObject&, NonnullRefPtrVector<Selector>&&, CSSStyleDeclaration&);
 
     virtual ~CSSStyleRule() override = default;
 
@@ -39,10 +39,11 @@ public:
     CSSStyleDeclaration* style();
 
 private:
+    virtual void visit_edges(Cell::Visitor&) override;
     virtual String serialized() const override;
 
     NonnullRefPtrVector<Selector> m_selectors;
-    NonnullRefPtr<CSSStyleDeclaration> m_declaration;
+    CSSStyleDeclaration& m_declaration;
 };
 
 template<>
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
index e32ae4efdb..5c28c2be49 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
@@ -2320,7 +2320,7 @@ Vector<Vector<ComponentValue>> Parser::parse_a_comma_separated_list_of_component
     return list_of_component_value_lists;
 }
 
-RefPtr<ElementInlineCSSStyleDeclaration> Parser::parse_as_style_attribute(DOM::Element& element)
+ElementInlineCSSStyleDeclaration* Parser::parse_as_style_attribute(DOM::Element& element)
 {
     auto declarations_and_at_rules = parse_a_list_of_declarations(m_token_stream);
     auto [properties, custom_properties] = extract_properties(declarations_and_at_rules);
@@ -2706,13 +2706,13 @@ CSSRule* Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
         auto stream = TokenStream(rule->block()->values());
         auto declarations_and_at_rules = parse_a_style_blocks_contents(stream);
 
-        auto declaration = convert_to_style_declaration(declarations_and_at_rules);
+        auto* declaration = convert_to_style_declaration(declarations_and_at_rules);
         if (!declaration) {
             dbgln_if(CSS_PARSER_DEBUG, "CSSParser: style rule declaration invalid; discarding.");
             return {};
         }
 
-        return CSSStyleRule::create(m_context.window_object(), move(selectors.value()), move(*declaration));
+        return CSSStyleRule::create(m_context.window_object(), move(selectors.value()), *declaration);
     }
 
     return {};
@@ -2741,10 +2741,10 @@ auto Parser::extract_properties(Vector<DeclarationOrAtRule> const& declarations_
     return result;
 }
 
-RefPtr<PropertyOwningCSSStyleDeclaration> Parser::convert_to_style_declaration(Vector<DeclarationOrAtRule> declarations_and_at_rules)
+PropertyOwningCSSStyleDeclaration* Parser::convert_to_style_declaration(Vector<DeclarationOrAtRule> declarations_and_at_rules)
 {
     auto [properties, custom_properties] = extract_properties(declarations_and_at_rules);
-    return PropertyOwningCSSStyleDeclaration::create(move(properties), move(custom_properties));
+    return PropertyOwningCSSStyleDeclaration::create(m_context.window_object(), move(properties), move(custom_properties));
 }
 
 Optional<StyleProperty> Parser::convert_to_style_property(Declaration const& declaration)
@@ -6396,7 +6396,7 @@ CSS::CSSStyleSheet* parse_css_stylesheet(CSS::Parser::ParsingContext const& cont
     return parser.parse_as_css_stylesheet(location);
 }
 
-RefPtr<CSS::ElementInlineCSSStyleDeclaration> parse_css_style_attribute(CSS::Parser::ParsingContext const& context, StringView css, DOM::Element& element)
+CSS::ElementInlineCSSStyleDeclaration* parse_css_style_attribute(CSS::Parser::ParsingContext const& context, StringView css, DOM::Element& element)
 {
     if (css.is_empty())
         return CSS::ElementInlineCSSStyleDeclaration::create(element, {}, {});
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
index 5779008004..088756d81a 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
+++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
@@ -127,7 +127,7 @@ public:
     ~Parser() = default;
 
     CSSStyleSheet* parse_as_css_stylesheet(Optional<AK::URL> location);
-    RefPtr<ElementInlineCSSStyleDeclaration> parse_as_style_attribute(DOM::Element&);
+    ElementInlineCSSStyleDeclaration* parse_as_style_attribute(DOM::Element&);
     CSSRule* parse_as_css_rule();
     Optional<StyleProperty> parse_as_supports_condition();
 
@@ -240,7 +240,7 @@ private:
     Vector<FontFace::Source> parse_font_face_src(TokenStream<ComponentValue>&);
 
     CSSRule* convert_to_rule(NonnullRefPtr<Rule>);
-    RefPtr<PropertyOwningCSSStyleDeclaration> convert_to_style_declaration(Vector<DeclarationOrAtRule> declarations);
+    PropertyOwningCSSStyleDeclaration* convert_to_style_declaration(Vector<DeclarationOrAtRule> declarations);
     Optional<StyleProperty> convert_to_style_property(Declaration const&);
 
     class Dimension {
@@ -421,7 +421,7 @@ private:
 namespace Web {
 
 CSS::CSSStyleSheet* parse_css_stylesheet(CSS::Parser::ParsingContext const&, StringView, Optional<AK::URL> location = {});
-RefPtr<CSS::ElementInlineCSSStyleDeclaration> parse_css_style_attribute(CSS::Parser::ParsingContext const&, StringView, DOM::Element&);
+CSS::ElementInlineCSSStyleDeclaration* parse_css_style_attribute(CSS::Parser::ParsingContext const&, StringView, DOM::Element&);
 RefPtr<CSS::StyleValue> parse_css_value(CSS::Parser::ParsingContext const&, StringView, CSS::PropertyID property_id = CSS::PropertyID::Invalid);
 Optional<CSS::SelectorList> parse_selector(CSS::Parser::ParsingContext const&, StringView);
 CSS::CSSRule* parse_css_rule(CSS::Parser::ParsingContext const&, StringView);
diff --git a/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.cpp b/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.cpp
index 3e9e9f1573..061214295b 100644
--- a/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.cpp
+++ b/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.cpp
@@ -19,8 +19,15 @@
 
 namespace Web::CSS {
 
+ResolvedCSSStyleDeclaration* ResolvedCSSStyleDeclaration::create(DOM::Element& element)
+{
+    auto& window_object = element.document().preferred_window_object();
+    return window_object.heap().allocate<ResolvedCSSStyleDeclaration>(window_object.realm(), element);
+}
+
 ResolvedCSSStyleDeclaration::ResolvedCSSStyleDeclaration(DOM::Element& element)
-    : m_element(element)
+    : CSSStyleDeclaration(element.document().preferred_window_object())
+    , m_element(element)
 {
 }
 
diff --git a/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.h b/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.h
index 5845265abc..285e853bfd 100644
--- a/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.h
+++ b/Userland/Libraries/LibWeb/CSS/ResolvedCSSStyleDeclaration.h
@@ -11,11 +11,11 @@
 namespace Web::CSS {
 
 class ResolvedCSSStyleDeclaration final : public CSSStyleDeclaration {
+    JS_OBJECT(ResolvedCSSStyleDeclaration, CSSStyleDeclaration);
+
 public:
-    static NonnullRefPtr<ResolvedCSSStyleDeclaration> create(DOM::Element& element)
-    {
-        return adopt_ref(*new ResolvedCSSStyleDeclaration(element));
-    }
+    static ResolvedCSSStyleDeclaration* create(DOM::Element& element);
+    explicit ResolvedCSSStyleDeclaration(DOM::Element&);
 
     virtual ~ResolvedCSSStyleDeclaration() override = default;
 
@@ -28,8 +28,6 @@ public:
     virtual String serialized() const override;
 
 private:
-    explicit ResolvedCSSStyleDeclaration(DOM::Element&);
-
     RefPtr<StyleValue> style_value_for_property(Layout::NodeWithStyle const&, PropertyID) const;
 
     NonnullRefPtr<DOM::Element> m_element;
diff --git a/Userland/Libraries/LibWeb/DOM/Element.cpp b/Userland/Libraries/LibWeb/DOM/Element.cpp
index 988ce36726..753a915a27 100644
--- a/Userland/Libraries/LibWeb/DOM/Element.cpp
+++ b/Userland/Libraries/LibWeb/DOM/Element.cpp
@@ -295,7 +295,7 @@ RefPtr<Layout::Node> Element::create_layout_node_for_display_type(DOM::Document&
 
 CSS::CSSStyleDeclaration const* Element::inline_style() const
 {
-    return m_inline_style;
+    return m_inline_style.cell();
 }
 
 void Element::parse_attribute(FlyString const& name, String const& value)
@@ -311,9 +311,9 @@ void Element::parse_attribute(FlyString const& name, String const& value)
             m_class_list->associated_attribute_changed(value);
     } else if (name == HTML::AttributeNames::style) {
         // https://drafts.csswg.org/cssom/#ref-for-cssstyledeclaration-updating-flag
-        if (m_inline_style && m_inline_style->is_updating())
+        if (m_inline_style.cell() && m_inline_style->is_updating())
             return;
-        m_inline_style = parse_css_style_attribute(CSS::Parser::ParsingContext(document()), value, *this);
+        m_inline_style = JS::make_handle(parse_css_style_attribute(CSS::Parser::ParsingContext(document()), value, *this));
         set_needs_style_update(true);
     }
 }
@@ -321,8 +321,8 @@ void Element::parse_attribute(FlyString const& name, String const& value)
 void Element::did_remove_attribute(FlyString const& name)
 {
     if (name == HTML::AttributeNames::style) {
-        if (m_inline_style) {
-            m_inline_style = nullptr;
+        if (m_inline_style.cell()) {
+            m_inline_style = {};
             set_needs_style_update(true);
         }
     }
@@ -507,11 +507,11 @@ void Element::set_shadow_root(RefPtr<ShadowRoot> shadow_root)
     invalidate_style();
 }
 
-NonnullRefPtr<CSS::CSSStyleDeclaration> Element::style_for_bindings()
+CSS::CSSStyleDeclaration* Element::style_for_bindings()
 {
-    if (!m_inline_style)
-        m_inline_style = CSS::ElementInlineCSSStyleDeclaration::create(*this, {}, {});
-    return *m_inline_style;
+    if (m_inline_style.is_null())
+        m_inline_style = JS::make_handle(CSS::ElementInlineCSSStyleDeclaration::create(*this, {}, {}));
+    return m_inline_style.cell();
 }
 
 // https://dom.spec.whatwg.org/#element-html-uppercased-qualified-name
diff --git a/Userland/Libraries/LibWeb/DOM/Element.h b/Userland/Libraries/LibWeb/DOM/Element.h
index d6b510ad6c..6c6b7a1db3 100644
--- a/Userland/Libraries/LibWeb/DOM/Element.h
+++ b/Userland/Libraries/LibWeb/DOM/Element.h
@@ -105,7 +105,7 @@ public:
 
     CSS::CSSStyleDeclaration const* inline_style() const;
 
-    NonnullRefPtr<CSS::CSSStyleDeclaration> style_for_bindings();
+    CSS::CSSStyleDeclaration* style_for_bindings();
 
     String inner_html() const;
     ExceptionOr<void> set_inner_html(String const&);
@@ -152,7 +152,7 @@ private:
     String m_html_uppercased_qualified_name;
     NonnullRefPtr<NamedNodeMap> m_attributes;
 
-    RefPtr<CSS::ElementInlineCSSStyleDeclaration> m_inline_style;
+    JS::Handle<CSS::ElementInlineCSSStyleDeclaration> m_inline_style;
 
     RefPtr<CSS::StyleProperties> m_computed_css_values;
     HashMap<FlyString, CSS::StyleProperty> m_custom_properties;
diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index f847f72348..eb06ef7f75 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -459,7 +459,6 @@ class CharacterDataWrapper;
 class CloseEventWrapper;
 class CommentWrapper;
 class CryptoWrapper;
-class CSSStyleDeclarationWrapper;
 class CustomEventWrapper;
 class DocumentFragmentWrapper;
 class DocumentTypeWrapper;
diff --git a/Userland/Libraries/LibWeb/HTML/Window.cpp b/Userland/Libraries/LibWeb/HTML/Window.cpp
index c1e2afaec6..2916345848 100644
--- a/Userland/Libraries/LibWeb/HTML/Window.cpp
+++ b/Userland/Libraries/LibWeb/HTML/Window.cpp
@@ -319,7 +319,7 @@ Page const* Window::page() const
     return associated_document().page();
 }
 
-NonnullRefPtr<CSS::CSSStyleDeclaration> Window::get_computed_style(DOM::Element& element) const
+CSS::CSSStyleDeclaration* Window::get_computed_style(DOM::Element& element) const
 {
     return CSS::ResolvedCSSStyleDeclaration::create(element);
 }
diff --git a/Userland/Libraries/LibWeb/HTML/Window.h b/Userland/Libraries/LibWeb/HTML/Window.h
index a1284ba8aa..be5b9793ed 100644
--- a/Userland/Libraries/LibWeb/HTML/Window.h
+++ b/Userland/Libraries/LibWeb/HTML/Window.h
@@ -95,7 +95,7 @@ public:
     DOM::Event const* current_event() const { return m_current_event; }
     void set_current_event(DOM::Event* event) { m_current_event = event; }
 
-    NonnullRefPtr<CSS::CSSStyleDeclaration> get_computed_style(DOM::Element&) const;
+    CSS::CSSStyleDeclaration* get_computed_style(DOM::Element&) const;
     NonnullRefPtr<CSS::MediaQueryList> match_media(String);
     Optional<CSS::MediaFeatureValue> query_media_feature(CSS::MediaFeatureID) const;
 
diff --git a/Userland/Libraries/LibWeb/idl_files.cmake b/Userland/Libraries/LibWeb/idl_files.cmake
index ac32cd609b..2cd19c0df9 100644
--- a/Userland/Libraries/LibWeb/idl_files.cmake
+++ b/Userland/Libraries/LibWeb/idl_files.cmake
@@ -10,7 +10,7 @@ libweb_js_wrapper(CSS/CSSImportRule NO_INSTANCE)
 libweb_js_wrapper(CSS/CSSMediaRule NO_INSTANCE)
 libweb_js_wrapper(CSS/CSSRule NO_INSTANCE)
 libweb_js_wrapper(CSS/CSSRuleList NO_INSTANCE)
-libweb_js_wrapper(CSS/CSSStyleDeclaration)
+libweb_js_wrapper(CSS/CSSStyleDeclaration NO_INSTANCE)
 libweb_js_wrapper(CSS/CSSStyleRule NO_INSTANCE)
 libweb_js_wrapper(CSS/CSSStyleSheet NO_INSTANCE)
 libweb_js_wrapper(CSS/CSSSupportsRule NO_INSTANCE)