LibWeb: Make CSSRule and all its subclasses GC-allocated

39 files changed, 338 insertions, 236 deletions

diff --git a/Documentation/Browser/AddNewIDLFile.md b/Documentation/Browser/AddNewIDLFile.md
index 1024e728c6..54f6e455bd 100644
--- a/Documentation/Browser/AddNewIDLFile.md
+++ b/Documentation/Browser/AddNewIDLFile.md
@@ -39,7 +39,6 @@ interface CSSRule {
    - It must have a public `using WrapperType = Bindings::HTMLDetailsElementWrapper;`
 
 7. Depending on what kind of thing your interface is, you may need to add it to the `WrapperFactory` of that kind:
-   - CSSRules: [`LibWeb/Bindings/CSSRuleWrapperFactory.cpp`](../../Userland/Libraries/LibWeb/Bindings/CSSRuleWrapperFactory.cpp)
    - Events: [`LibWeb/Bindings/EventWrapperFactory.cpp`](../../Userland/Libraries/LibWeb/Bindings/EventWrapperFactory.cpp)
    - Elements: [`LibWeb/Bindings/NodeWrapperFactory.cpp`](../../Userland/Libraries/LibWeb/Bindings/NodeWrapperFactory.cpp)
 
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/WrapperGenerator/IDLGenerators.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/WrapperGenerator/IDLGenerators.cpp
index 8b22a1b2e4..14020284c1 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/WrapperGenerator/IDLGenerators.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/WrapperGenerator/IDLGenerators.cpp
@@ -87,6 +87,27 @@ static bool impl_is_wrapper(Type const& type)
     if (type.name == "CSSRuleList"sv)
         return true;
 
+    if (type.name == "CSSRule"sv)
+        return true;
+
+    if (type.name == "CSSStyleRule"sv)
+        return true;
+
+    if (type.name == "CSSFontFaceRule"sv)
+        return true;
+
+    if (type.name == "CSSConditionRule"sv)
+        return true;
+
+    if (type.name == "CSSGroupingRule"sv)
+        return true;
+
+    if (type.name == "CSSMediaRule"sv)
+        return true;
+
+    if (type.name == "CSSImportRule"sv)
+        return true;
+
     return false;
 }
 
@@ -2884,7 +2905,6 @@ void generate_constructor_implementation(IDL::Interface const& interface)
 #if __has_include(<LibWeb/Bindings/@wrapper_class@.h>)
 #include <LibWeb/Bindings/@wrapper_class@.h>
 #endif
-#include <LibWeb/Bindings/CSSRuleWrapperFactory.h>
 #include <LibWeb/Bindings/EventTargetWrapperFactory.h>
 #include <LibWeb/Bindings/EventWrapperFactory.h>
 #include <LibWeb/Bindings/ExceptionOrUtils.h>
diff --git a/Userland/Libraries/LibWeb/Bindings/CSSRuleWrapperFactory.cpp b/Userland/Libraries/LibWeb/Bindings/CSSRuleWrapperFactory.cpp
deleted file mode 100644
index 2870c97f4c..0000000000
--- a/Userland/Libraries/LibWeb/Bindings/CSSRuleWrapperFactory.cpp
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#include <AK/TypeCasts.h>
-#include <LibWeb/Bindings/CSSFontFaceRuleWrapper.h>
-#include <LibWeb/Bindings/CSSImportRuleWrapper.h>
-#include <LibWeb/Bindings/CSSMediaRuleWrapper.h>
-#include <LibWeb/Bindings/CSSRuleWrapper.h>
-#include <LibWeb/Bindings/CSSRuleWrapperFactory.h>
-#include <LibWeb/Bindings/CSSStyleRuleWrapper.h>
-#include <LibWeb/Bindings/CSSSupportsRuleWrapper.h>
-#include <LibWeb/CSS/CSSFontFaceRule.h>
-#include <LibWeb/CSS/CSSImportRule.h>
-#include <LibWeb/CSS/CSSMediaRule.h>
-#include <LibWeb/CSS/CSSStyleRule.h>
-#include <LibWeb/CSS/CSSSupportsRule.h>
-
-namespace Web::Bindings {
-
-CSSRuleWrapper* wrap(JS::Realm& realm, CSS::CSSRule& rule)
-{
-    if (rule.wrapper())
-        return static_cast<CSSRuleWrapper*>(rule.wrapper());
-
-    if (is<CSS::CSSStyleRule>(rule))
-        return static_cast<CSSRuleWrapper*>(wrap_impl(realm, verify_cast<CSS::CSSStyleRule>(rule)));
-    if (is<CSS::CSSImportRule>(rule))
-        return static_cast<CSSRuleWrapper*>(wrap_impl(realm, verify_cast<CSS::CSSImportRule>(rule)));
-    if (is<CSS::CSSMediaRule>(rule))
-        return static_cast<CSSRuleWrapper*>(wrap_impl(realm, verify_cast<CSS::CSSMediaRule>(rule)));
-    if (is<CSS::CSSFontFaceRule>(rule))
-        return static_cast<CSSRuleWrapper*>(wrap_impl(realm, verify_cast<CSS::CSSFontFaceRule>(rule)));
-    if (is<CSS::CSSSupportsRule>(rule))
-        return static_cast<CSSRuleWrapper*>(wrap_impl(realm, verify_cast<CSS::CSSSupportsRule>(rule)));
-    return static_cast<CSSRuleWrapper*>(wrap_impl(realm, rule));
-}
-
-}
diff --git a/Userland/Libraries/LibWeb/Bindings/CSSRuleWrapperFactory.h b/Userland/Libraries/LibWeb/Bindings/CSSRuleWrapperFactory.h
deleted file mode 100644
index 2382bfef97..0000000000
--- a/Userland/Libraries/LibWeb/Bindings/CSSRuleWrapperFactory.h
+++ /dev/null
@@ -1,16 +0,0 @@
-/*
- * Copyright (c) 2021, Andreas Kling <kling@serenityos.org>
- *
- * SPDX-License-Identifier: BSD-2-Clause
- */
-
-#pragma once
-
-#include <LibJS/Forward.h>
-#include <LibWeb/Forward.h>
-
-namespace Web::Bindings {
-
-CSSRuleWrapper* wrap(JS::Realm&, CSS::CSSRule&);
-
-}
diff --git a/Userland/Libraries/LibWeb/CMakeLists.txt b/Userland/Libraries/LibWeb/CMakeLists.txt
index 4983599a2c..65e039f404 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/CSSRuleWrapperFactory.cpp
     Bindings/CSSStyleDeclarationWrapperCustom.cpp
     Bindings/EventListenerWrapper.cpp
     Bindings/EventTargetWrapperFactory.cpp
diff --git a/Userland/Libraries/LibWeb/CSS/CSSConditionRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSConditionRule.cpp
index f6ac1a254b..cd10d45401 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSConditionRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSConditionRule.cpp
@@ -1,16 +1,20 @@
 /*
  * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSConditionRulePrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSConditionRule.h>
 
 namespace Web::CSS {
 
-CSSConditionRule::CSSConditionRule(NonnullRefPtrVector<CSSRule>&& rules)
-    : CSSGroupingRule(move(rules))
+CSSConditionRule::CSSConditionRule(Bindings::WindowObject& window_object, CSSRuleList& rules)
+    : CSSGroupingRule(window_object, rules)
 {
+    set_prototype(&window_object.ensure_web_prototype<Bindings::CSSConditionRulePrototype>("CSSConditionRule"));
 }
 
 void CSSConditionRule::for_each_effective_style_rule(Function<void(CSSStyleRule const&)> const& callback) const
diff --git a/Userland/Libraries/LibWeb/CSS/CSSConditionRule.h b/Userland/Libraries/LibWeb/CSS/CSSConditionRule.h
index 6cf61c2219..58d040a5ee 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSConditionRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSConditionRule.h
@@ -15,9 +15,10 @@ namespace Web::CSS {
 class CSSConditionRule : public CSSGroupingRule {
     AK_MAKE_NONCOPYABLE(CSSConditionRule);
     AK_MAKE_NONMOVABLE(CSSConditionRule);
+    JS_OBJECT(CSSConditionRule, CSSGroupingRule);
 
 public:
-    using WrapperType = Bindings::CSSConditionRuleWrapper;
+    CSSConditionRule& impl() { return *this; }
 
     virtual ~CSSConditionRule() = default;
 
@@ -28,7 +29,12 @@ public:
     virtual void for_each_effective_style_rule(Function<void(CSSStyleRule const&)> const& callback) const override;
 
 protected:
-    explicit CSSConditionRule(NonnullRefPtrVector<CSSRule>&&);
+    explicit CSSConditionRule(Bindings::WindowObject&, CSSRuleList&);
 };
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSConditionRule& object) { return &object; }
+using CSSConditionRuleWrapper = Web::CSS::CSSConditionRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSConditionRule.idl b/Userland/Libraries/LibWeb/CSS/CSSConditionRule.idl
index 73c336eaaa..ad01e7db8e 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSConditionRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSConditionRule.idl
@@ -1,6 +1,6 @@
 #import <CSS/CSSGroupingRule.idl>
 
-[Exposed=Window]
+[Exposed=Window, NoInstanceWrapper]
 interface CSSConditionRule : CSSGroupingRule {
     attribute CSSOMString conditionText;
 };
diff --git a/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.cpp
index f001068142..f6b3f69086 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.cpp
@@ -1,16 +1,26 @@
 /*
  * Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSFontFaceRulePrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSFontFaceRule.h>
 
 namespace Web::CSS {
 
-CSSFontFaceRule::CSSFontFaceRule(FontFace&& font_face)
-    : m_font_face(move(font_face))
+CSSFontFaceRule* CSSFontFaceRule::create(Bindings::WindowObject& window_object, FontFace&& font_face)
 {
+    return window_object.heap().allocate<CSSFontFaceRule>(window_object.realm(), window_object, move(font_face));
+}
+
+CSSFontFaceRule::CSSFontFaceRule(Bindings::WindowObject& window_object, FontFace&& font_face)
+    : CSSRule(window_object)
+    , m_font_face(move(font_face))
+{
+    set_prototype(&window_object.ensure_web_prototype<Bindings::CSSFontFaceRulePrototype>("CSSFontFaceRule"));
 }
 
 CSSStyleDeclaration* CSSFontFaceRule::style()
diff --git a/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.h b/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.h
index 80b8866dc3..5967add8fc 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -14,26 +15,21 @@ namespace Web::CSS {
 class CSSFontFaceRule final : public CSSRule {
     AK_MAKE_NONCOPYABLE(CSSFontFaceRule);
     AK_MAKE_NONMOVABLE(CSSFontFaceRule);
+    JS_OBJECT(CSSFontFaceRule, CSSRule);
 
 public:
-    using WrapperType = Bindings::CSSFontFaceRuleWrapper;
-
-    static NonnullRefPtr<CSSFontFaceRule> create(FontFace&& font_face)
-    {
-        return adopt_ref(*new CSSFontFaceRule(move(font_face)));
-    }
+    static CSSFontFaceRule* create(Bindings::WindowObject&, FontFace&&);
+    explicit CSSFontFaceRule(Bindings::WindowObject&, FontFace&&);
 
     virtual ~CSSFontFaceRule() override = default;
+    CSSFontFaceRule& impl() { return *this; }
 
-    virtual StringView class_name() const override { return "CSSFontFaceRule"sv; }
     virtual Type type() const override { return Type::FontFace; }
 
     FontFace const& font_face() const { return m_font_face; }
     CSSStyleDeclaration* style();
 
 private:
-    explicit CSSFontFaceRule(FontFace&&);
-
     virtual String serialized() const override;
 
     FontFace m_font_face;
@@ -43,3 +39,8 @@ template<>
 inline bool CSSRule::fast_is<CSSFontFaceRule>() const { return type() == CSSRule::Type::FontFace; }
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSFontFaceRule& object) { return &object; }
+using CSSFontFaceRuleWrapper = Web::CSS::CSSFontFaceRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.idl b/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.idl
index cf5701a19b..3dd9926ec3 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSFontFaceRule.idl
@@ -1,7 +1,7 @@
 #import <CSS/CSSRule.idl>
 #import <CSS/CSSStyleDeclaration.idl>
 
-[Exposed=Window]
+[Exposed=Window, NoInstanceWrapper]
 interface CSSFontFaceRule : CSSRule {
     readonly attribute CSSStyleDeclaration style;
 };
diff --git a/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.cpp
index bb214da973..e852b1ff44 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.cpp
@@ -1,45 +1,55 @@
 /*
  * Copyright (c) 2021-2022, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSGroupingRulePrototype.h>
 #include <LibWeb/Bindings/MainThreadVM.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSGroupingRule.h>
 #include <LibWeb/CSS/CSSRuleList.h>
 
 namespace Web::CSS {
 
-CSSGroupingRule::CSSGroupingRule(NonnullRefPtrVector<CSSRule>&& rules)
-    // FIXME: Use the same window object for the rule list.
-    : m_rules(JS::make_handle(CSSRuleList::create(Bindings::main_thread_internal_window_object(), move(rules))))
+CSSGroupingRule::CSSGroupingRule(Bindings::WindowObject& window_object, CSSRuleList& rules)
+    : CSSRule(window_object)
+    , m_rules(rules)
 {
-    for (auto& rule : *m_rules)
+    set_prototype(&window_object.ensure_web_prototype<Bindings::CSSGroupingRulePrototype>("CSSGroupingRule"));
+    for (auto& rule : m_rules)
         rule.set_parent_rule(this);
 }
 
+void CSSGroupingRule::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(&m_rules);
+}
+
 DOM::ExceptionOr<u32> CSSGroupingRule::insert_rule(StringView rule, u32 index)
 {
-    TRY(m_rules->insert_a_css_rule(rule, index));
+    TRY(m_rules.insert_a_css_rule(rule, index));
     // NOTE: The spec doesn't say where to set the parent rule, so we'll do it here.
-    m_rules->item(index)->set_parent_rule(this);
+    m_rules.item(index)->set_parent_rule(this);
     return index;
 }
 
 DOM::ExceptionOr<void> CSSGroupingRule::delete_rule(u32 index)
 {
-    return m_rules->remove_a_css_rule(index);
+    return m_rules.remove_a_css_rule(index);
 }
 
 void CSSGroupingRule::for_each_effective_style_rule(Function<void(CSSStyleRule const&)> const& callback) const
 {
-    m_rules->for_each_effective_style_rule(callback);
+    m_rules.for_each_effective_style_rule(callback);
 }
 
 void CSSGroupingRule::set_parent_style_sheet(CSSStyleSheet* parent_style_sheet)
 {
     CSSRule::set_parent_style_sheet(parent_style_sheet);
-    for (auto& rule : *m_rules)
+    for (auto& rule : m_rules)
         rule.set_parent_style_sheet(parent_style_sheet);
 }
 
diff --git a/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.h b/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.h
index 19dae632d3..271572d226 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.h
@@ -17,15 +17,16 @@ namespace Web::CSS {
 class CSSGroupingRule : public CSSRule {
     AK_MAKE_NONCOPYABLE(CSSGroupingRule);
     AK_MAKE_NONMOVABLE(CSSGroupingRule);
+    JS_OBJECT(CSSGroupingRule, CSSRule);
 
 public:
-    using WrapperType = Bindings::CSSGroupingRuleWrapper;
+    CSSGroupingRule& impl() { return *this; }
 
     virtual ~CSSGroupingRule() = default;
 
-    CSSRuleList const& css_rules() const { return *m_rules; }
-    CSSRuleList& css_rules() { return *m_rules; }
-    CSSRuleList* css_rules_for_bindings() { return m_rules.cell(); }
+    CSSRuleList const& css_rules() const { return m_rules; }
+    CSSRuleList& css_rules() { return m_rules; }
+    CSSRuleList* css_rules_for_bindings() { return &m_rules; }
     DOM::ExceptionOr<u32> insert_rule(StringView rule, u32 index = 0);
     DOM::ExceptionOr<void> delete_rule(u32 index);
 
@@ -34,10 +35,17 @@ public:
     virtual void set_parent_style_sheet(CSSStyleSheet*) override;
 
 protected:
-    explicit CSSGroupingRule(NonnullRefPtrVector<CSSRule>&&);
+    explicit CSSGroupingRule(Bindings::WindowObject&, CSSRuleList&);
 
 private:
-    JS::Handle<CSSRuleList> m_rules;
+    virtual void visit_edges(Cell::Visitor&) override;
+
+    CSSRuleList& m_rules;
 };
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSGroupingRule& object) { return &object; }
+using CSSGroupingRuleWrapper = Web::CSS::CSSGroupingRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.idl b/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.idl
index 6f8280a0fd..7a1c3e3d00 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSGroupingRule.idl
@@ -1,7 +1,7 @@
 #import <CSS/CSSRule.idl>
 #import <CSS/CSSRuleList.idl>
 
-[Exposed=Window]
+[Exposed=Window, NoInstanceWrapper]
 interface CSSGroupingRule : CSSRule {
     [SameObject, ImplementedAs=css_rules_for_bindings] readonly attribute CSSRuleList cssRules;
     unsigned long insertRule(CSSOMString rule, optional unsigned long index = 0);
diff --git a/Userland/Libraries/LibWeb/CSS/CSSImportRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSImportRule.cpp
index 61ea65e7bc..52c25953bb 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSImportRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSImportRule.cpp
@@ -1,12 +1,15 @@
 /*
  * Copyright (c) 2021, the SerenityOS developers.
  * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #include <AK/Debug.h>
 #include <AK/URL.h>
+#include <LibWeb/Bindings/CSSImportRulePrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSImportRule.h>
 #include <LibWeb/CSS/Parser/Parser.h>
 #include <LibWeb/DOM/Document.h>
@@ -14,10 +17,19 @@
 
 namespace Web::CSS {
 
+CSSImportRule* CSSImportRule::create(AK::URL url, DOM::Document& document)
+{
+    auto& window_object = document.preferred_window_object();
+    return window_object.heap().allocate<CSSImportRule>(window_object.realm(), move(url), document);
+}
+
 CSSImportRule::CSSImportRule(AK::URL url, DOM::Document& document)
-    : m_url(move(url))
+    : CSSRule(document.preferred_window_object())
+    , m_url(move(url))
     , m_document(document)
 {
+    set_prototype(&document.preferred_window_object().ensure_web_prototype<Bindings::CSSImportRulePrototype>("CSSImportRule"));
+
     dbgln_if(CSS_LOADER_DEBUG, "CSSImportRule: Loading import URL: {}", m_url);
     auto request = LoadRequest::create_for_url_on_page(m_url, document.page());
 
@@ -28,6 +40,12 @@ CSSImportRule::CSSImportRule(AK::URL url, DOM::Document& document)
     set_resource(ResourceLoader::the().load_resource(Resource::Type::Generic, request));
 }
 
+void CSSImportRule::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_style_sheet);
+}
+
 // https://www.w3.org/TR/cssom/#serialize-a-css-rule
 String CSSImportRule::serialized() const
 {
@@ -79,7 +97,7 @@ void CSSImportRule::resource_did_load()
         return;
     }
 
-    m_style_sheet = JS::make_handle(sheet);
+    m_style_sheet = sheet;
 
     m_document->style_computer().invalidate_rule_cache();
     m_document->invalidate_style();
diff --git a/Userland/Libraries/LibWeb/CSS/CSSImportRule.h b/Userland/Libraries/LibWeb/CSS/CSSImportRule.h
index abe16dfb73..ac2cb26a38 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSImportRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSImportRule.h
@@ -1,6 +1,7 @@
 /*
  * Copyright (c) 2021, the SerenityOS developers.
  * Copyright (c) 2021-2022, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -20,32 +21,30 @@ class CSSImportRule final
     , public ResourceClient {
     AK_MAKE_NONCOPYABLE(CSSImportRule);
     AK_MAKE_NONMOVABLE(CSSImportRule);
+    JS_OBJECT(CSSImportRule, CSSRule);
 
 public:
-    using WrapperType = Bindings::CSSImportRuleWrapper;
-
-    static NonnullRefPtr<CSSImportRule> create(AK::URL url, DOM::Document& document)
-    {
-        return adopt_ref(*new CSSImportRule(move(url), document));
-    }
+    static CSSImportRule* create(AK::URL, DOM::Document&);
+    CSSImportRule(AK::URL, DOM::Document&);
 
     virtual ~CSSImportRule() = default;
 
+    CSSImportRule& impl() { return *this; }
+
     AK::URL const& url() const { return m_url; }
     // FIXME: This should return only the specified part of the url. eg, "stuff/foo.css", not "https://example.com/stuff/foo.css".
     String href() const { return m_url.to_string(); }
 
-    bool has_import_result() const { return !m_style_sheet.is_null(); }
-    CSSStyleSheet* loaded_style_sheet() { return m_style_sheet.cell(); }
-    CSSStyleSheet const* loaded_style_sheet() const { return m_style_sheet.cell(); }
-    CSSStyleSheet* style_sheet_for_bindings() { return m_style_sheet.cell(); }
-    void set_style_sheet(CSSStyleSheet* style_sheet) { m_style_sheet = JS::make_handle(style_sheet); }
+    bool has_import_result() const { return !m_style_sheet; }
+    CSSStyleSheet* loaded_style_sheet() { return m_style_sheet; }
+    CSSStyleSheet const* loaded_style_sheet() const { return m_style_sheet; }
+    CSSStyleSheet* style_sheet_for_bindings() { return m_style_sheet; }
+    void set_style_sheet(CSSStyleSheet* style_sheet) { m_style_sheet = style_sheet; }
 
-    virtual StringView class_name() const override { return "CSSImportRule"sv; };
     virtual Type type() const override { return Type::Import; };
 
 private:
-    explicit CSSImportRule(AK::URL, DOM::Document&);
+    virtual void visit_edges(Cell::Visitor&) override;
 
     virtual String serialized() const override;
 
@@ -56,10 +55,15 @@ private:
     AK::URL m_url;
     WeakPtr<DOM::Document> m_document;
     Optional<DOM::DocumentLoadEventDelayer> m_document_load_event_delayer;
-    JS::Handle<CSSStyleSheet> m_style_sheet;
+    CSSStyleSheet* m_style_sheet { nullptr };
 };
 
 template<>
 inline bool CSSRule::fast_is<CSSImportRule>() const { return type() == CSSRule::Type::Import; }
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSImportRule& object) { return &object; }
+using CSSImportRuleWrapper = Web::CSS::CSSImportRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSImportRule.idl b/Userland/Libraries/LibWeb/CSS/CSSImportRule.idl
index 838e64d77a..e274ff93b8 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSImportRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSImportRule.idl
@@ -2,7 +2,7 @@
 #import <CSS/CSSStyleSheet.idl>
 #import <CSS/MediaList.idl>
 
-[Exposed=Window]
+[Exposed=Window, NoInstanceWrapper]
 interface CSSImportRule : CSSRule {
     readonly attribute USVString href;
     // [SameObject, PutForwards=mediaText] readonly attribute MediaList media;
diff --git a/Userland/Libraries/LibWeb/CSS/CSSMediaRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSMediaRule.cpp
index 3e5361817e..698e563fa6 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSMediaRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSMediaRule.cpp
@@ -1,17 +1,26 @@
 /*
  * Copyright (c) 2021, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSMediaRulePrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSMediaRule.h>
 
 namespace Web::CSS {
 
-CSSMediaRule::CSSMediaRule(NonnullRefPtr<MediaList>&& media, NonnullRefPtrVector<CSSRule>&& rules)
-    : CSSConditionRule(move(rules))
+CSSMediaRule* CSSMediaRule::create(Bindings::WindowObject& window_object, NonnullRefPtr<MediaList>&& media_queries, CSSRuleList& rules)
+{
+    return window_object.heap().allocate<CSSMediaRule>(window_object.realm(), window_object, move(media_queries), rules);
+}
+
+CSSMediaRule::CSSMediaRule(Bindings::WindowObject& window_object, NonnullRefPtr<MediaList>&& media, CSSRuleList& rules)
+    : CSSConditionRule(window_object, rules)
     , m_media(move(media))
 {
+    set_prototype(&window_object.ensure_web_prototype<Bindings::CSSMediaRulePrototype>("CSSMediaRule"));
 }
 
 String CSSMediaRule::condition_text() const
diff --git a/Userland/Libraries/LibWeb/CSS/CSSMediaRule.h b/Userland/Libraries/LibWeb/CSS/CSSMediaRule.h
index 3bd7214243..f3563660d2 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSMediaRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSMediaRule.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2021-2022, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -16,18 +17,16 @@ namespace Web::CSS {
 class CSSMediaRule final : public CSSConditionRule {
     AK_MAKE_NONCOPYABLE(CSSMediaRule);
     AK_MAKE_NONMOVABLE(CSSMediaRule);
+    JS_OBJECT(CSSMediaRule, CSSConditionRule);
 
 public:
-    using WrapperType = Bindings::CSSMediaRuleWrapper;
+    CSSMediaRule& impl() { return *this; }
 
-    static NonnullRefPtr<CSSMediaRule> create(NonnullRefPtr<MediaList>&& media_queries, NonnullRefPtrVector<CSSRule>&& rules)
-    {
-        return adopt_ref(*new CSSMediaRule(move(media_queries), move(rules)));
-    }
+    static CSSMediaRule* create(Bindings::WindowObject&, NonnullRefPtr<MediaList>&& media_queries, CSSRuleList&);
+    explicit CSSMediaRule(Bindings::WindowObject&, NonnullRefPtr<MediaList>&&, CSSRuleList&);
 
     virtual ~CSSMediaRule() = default;
 
-    virtual StringView class_name() const override { return "CSSMediaRule"sv; };
     virtual Type type() const override { return Type::Media; };
 
     virtual String condition_text() const override;
@@ -39,8 +38,6 @@ public:
     bool evaluate(HTML::Window const& window) { return m_media->evaluate(window); }
 
 private:
-    explicit CSSMediaRule(NonnullRefPtr<MediaList>&&, NonnullRefPtrVector<CSSRule>&&);
-
     virtual String serialized() const override;
 
     NonnullRefPtr<MediaList> m_media;
@@ -50,3 +47,8 @@ template<>
 inline bool CSSRule::fast_is<CSSMediaRule>() const { return type() == CSSRule::Type::Media; }
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSMediaRule& object) { return &object; }
+using CSSMediaRuleWrapper = Web::CSS::CSSMediaRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSMediaRule.idl b/Userland/Libraries/LibWeb/CSS/CSSMediaRule.idl
index 72e3c55454..60fda190c1 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSMediaRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSMediaRule.idl
@@ -1,7 +1,7 @@
 #import <CSS/CSSConditionRule.idl>
 #import <CSS/MediaList.idl>
 
-[Exposed=Window]
+[Exposed=Window, NoInstanceWrapper]
 interface CSSMediaRule : CSSConditionRule {
     [SameObject, PutForwards=mediaText] readonly attribute MediaList media;
 };
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSRule.cpp
index bd1b94493a..b3c8fcf351 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSRule.cpp
@@ -1,15 +1,30 @@
 /*
  * Copyright (c) 2021, the SerenityOS developers.
  * Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSRulePrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSRule.h>
 #include <LibWeb/CSS/CSSStyleSheet.h>
 
 namespace Web::CSS {
 
+CSSRule::CSSRule(Bindings::WindowObject& window_object)
+    : PlatformObject(window_object.ensure_web_prototype<Bindings::CSSRulePrototype>("CSSRule"))
+{
+}
+
+void CSSRule::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_parent_style_sheet.ptr());
+    visitor.visit(m_parent_rule.ptr());
+}
+
 // https://www.w3.org/TR/cssom/#dom-cssrule-csstext
 String CSSRule::css_text() const
 {
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRule.h b/Userland/Libraries/LibWeb/CSS/CSSRule.h
index 986dc3a6e6..7b82ba62ce 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSRule.h
@@ -1,27 +1,25 @@
 /*
  * Copyright (c) 2021, the SerenityOS developers.
+ * Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #pragma once
 
-#include <AK/RefCounted.h>
 #include <AK/String.h>
-#include <AK/Weakable.h>
-#include <LibWeb/Bindings/Wrappable.h>
+#include <LibJS/Heap/GCPtr.h>
+#include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/CSS/CSSStyleDeclaration.h>
 #include <LibWeb/CSS/Selector.h>
 
 namespace Web::CSS {
 
-class CSSRule
-    : public RefCounted<CSSRule>
-    , public Bindings::Wrappable
-    , public Weakable<CSSRule> {
-public:
-    using WrapperType = Bindings::CSSRuleWrapper;
+class CSSRule : public Bindings::PlatformObject {
+    JS_OBJECT(CSSRule, JS::Object);
 
+public:
+    CSSRule& impl() { return *this; }
     virtual ~CSSRule() = default;
 
     // https://drafts.csswg.org/cssom/#dom-cssrule-type
@@ -33,26 +31,34 @@ public:
         Supports = 12,
     };
 
-    virtual StringView class_name() const = 0;
     virtual Type type() const = 0;
 
     String css_text() const;
     void set_css_text(StringView);
 
-    CSSRule* parent_rule() { return m_parent_rule; }
+    CSSRule* parent_rule() { return m_parent_rule.ptr(); }
     void set_parent_rule(CSSRule*);
 
-    CSSStyleSheet* parent_style_sheet() { return m_parent_style_sheet; }
+    CSSStyleSheet* parent_style_sheet() { return m_parent_style_sheet.ptr(); }
     virtual void set_parent_style_sheet(CSSStyleSheet*);
 
     template<typename T>
     bool fast_is() const = delete;
 
 protected:
+    explicit CSSRule(Bindings::WindowObject&);
+
     virtual String serialized() const = 0;
 
-    WeakPtr<CSSRule> m_parent_rule;
-    WeakPtr<CSSStyleSheet> m_parent_style_sheet;
+    virtual void visit_edges(Cell::Visitor&) override;
+
+    JS::GCPtr<CSSRule> m_parent_rule;
+    JS::GCPtr<CSSStyleSheet> m_parent_style_sheet;
 };
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSRule& object) { return &object; }
+using CSSRuleWrapper = Web::CSS::CSSRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRule.idl b/Userland/Libraries/LibWeb/CSS/CSSRule.idl
index bd40b41bd6..e7e262bc32 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSRule.idl
@@ -1,6 +1,6 @@
 #import <CSS/CSSStyleSheet.idl>
 
-[Exposed=Window]
+[Exposed=Window, NoInstanceWrapper]
 interface CSSRule {
 
     attribute CSSOMString cssText;
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp b/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp
index b076c58feb..8aa7bf293c 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSRuleList.cpp
@@ -9,23 +9,38 @@
 #include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSImportRule.h>
 #include <LibWeb/CSS/CSSMediaRule.h>
+#include <LibWeb/CSS/CSSRule.h>
 #include <LibWeb/CSS/CSSRuleList.h>
 #include <LibWeb/CSS/CSSSupportsRule.h>
 #include <LibWeb/CSS/Parser/Parser.h>
 
 namespace Web::CSS {
 
-CSSRuleList* CSSRuleList::create(Bindings::WindowObject& window_object, NonnullRefPtrVector<Web::CSS::CSSRule>&& rules)
+CSSRuleList* CSSRuleList::create(Bindings::WindowObject& window_object, JS::MarkedVector<CSSRule*> const& rules)
 {
-    return window_object.heap().allocate<CSSRuleList>(window_object.realm(), window_object, move(rules));
+    auto* rule_list = window_object.heap().allocate<CSSRuleList>(window_object.realm(), window_object);
+    for (auto* rule : rules)
+        rule_list->m_rules.append(*rule);
+    return rule_list;
 }
 
-CSSRuleList::CSSRuleList(Bindings::WindowObject& window_object, NonnullRefPtrVector<CSSRule>&& rules)
+CSSRuleList::CSSRuleList(Bindings::WindowObject& window_object)
     : Bindings::LegacyPlatformObject(window_object.ensure_web_prototype<Bindings::CSSRuleListPrototype>("CSSRuleList"))
-    , m_rules(move(rules))
 {
 }
 
+CSSRuleList* CSSRuleList::create_empty(Bindings::WindowObject& window_object)
+{
+    return window_object.heap().allocate<CSSRuleList>(window_object.realm(), window_object);
+}
+
+void CSSRuleList::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    for (auto& rule : m_rules)
+        visitor.visit(&rule);
+}
+
 bool CSSRuleList::is_supported_property_index(u32 index) const
 {
     // The object’s supported property indices are the numbers in the range zero to one less than the number of CSSRule objects represented by the collection.
@@ -34,7 +49,7 @@ bool CSSRuleList::is_supported_property_index(u32 index) const
 }
 
 // https://www.w3.org/TR/cssom/#insert-a-css-rule
-DOM::ExceptionOr<unsigned> CSSRuleList::insert_a_css_rule(Variant<StringView, NonnullRefPtr<CSSRule>> rule, u32 index)
+DOM::ExceptionOr<unsigned> CSSRuleList::insert_a_css_rule(Variant<StringView, CSSRule*> rule, u32 index)
 {
     // 1. Set length to the number of items in list.
     auto length = m_rules.size();
@@ -47,11 +62,13 @@ DOM::ExceptionOr<unsigned> CSSRuleList::insert_a_css_rule(Variant<StringView, No
     // NOTE: The insert-a-css-rule spec expects `rule` to be a string, but the CSSStyleSheet.insertRule()
     //       spec calls this algorithm with an already-parsed CSSRule. So, we use a Variant and skip step 3
     //       if that variant holds a CSSRule already.
-    RefPtr<CSSRule> new_rule;
+    CSSRule* new_rule = nullptr;
     if (rule.has<StringView>()) {
-        new_rule = parse_css_rule(CSS::Parser::ParsingContext {}, rule.get<StringView>());
+        new_rule = parse_css_rule(
+            CSS::Parser::ParsingContext { static_cast<Bindings::WindowObject&>(global_object()) },
+            rule.get<StringView>());
     } else {
-        new_rule = rule.get<NonnullRefPtr<CSSRule>>();
+        new_rule = rule.get<CSSRule*>();
     }
 
     // 4. If new rule is a syntax error, throw a SyntaxError exception.
@@ -63,7 +80,7 @@ DOM::ExceptionOr<unsigned> CSSRuleList::insert_a_css_rule(Variant<StringView, No
     // FIXME: 6. If new rule is an @namespace at-rule, and list contains anything other than @import at-rules, and @namespace at-rules, throw an InvalidStateError exception.
 
     // 7. Insert new rule into list at the zero-indexed position index.
-    m_rules.insert(index, new_rule.release_nonnull());
+    m_rules.insert(index, *new_rule);
 
     // 8. Return index.
     return index;
@@ -80,7 +97,7 @@ DOM::ExceptionOr<void> CSSRuleList::remove_a_css_rule(u32 index)
         return DOM::IndexSizeError::create("CSS rule index out of bounds.");
 
     // 3. Set old rule to the indexth item in list.
-    NonnullRefPtr<CSSRule> old_rule = m_rules[index];
+    CSSRule& old_rule = m_rules[index];
 
     // FIXME: 4. If old rule is an @namespace at-rule, and list contains anything other than @import at-rules, and @namespace at-rules, throw an InvalidStateError exception.
 
@@ -88,8 +105,8 @@ DOM::ExceptionOr<void> CSSRuleList::remove_a_css_rule(u32 index)
     m_rules.remove(index);
 
     // 6. Set old rule’s parent CSS rule and parent CSS style sheet to null.
-    old_rule->set_parent_rule(nullptr);
-    old_rule->set_parent_style_sheet(nullptr);
+    old_rule.set_parent_rule(nullptr);
+    old_rule.set_parent_style_sheet(nullptr);
 
     return {};
 }
@@ -102,7 +119,7 @@ void CSSRuleList::for_each_effective_style_rule(Function<void(CSSStyleRule const
             break;
         case CSSRule::Type::Import: {
             auto const& import_rule = static_cast<CSSImportRule const&>(rule);
-            if (import_rule.has_import_result())
+            if (import_rule.has_import_result() && import_rule.loaded_style_sheet())
                 import_rule.loaded_style_sheet()->for_each_effective_style_rule(callback);
             break;
         }
@@ -129,7 +146,7 @@ bool CSSRuleList::evaluate_media_queries(HTML::Window const& window)
             break;
         case CSSRule::Type::Import: {
             auto& import_rule = verify_cast<CSSImportRule>(rule);
-            if (import_rule.has_import_result() && import_rule.loaded_style_sheet()->evaluate_media_queries(window))
+            if (import_rule.has_import_result() && import_rule.loaded_style_sheet() && import_rule.loaded_style_sheet()->evaluate_media_queries(window))
                 any_media_queries_changed_match_state = true;
             break;
         }
diff --git a/Userland/Libraries/LibWeb/CSS/CSSRuleList.h b/Userland/Libraries/LibWeb/CSS/CSSRuleList.h
index af4157f61b..9f94bcc1d4 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSRuleList.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSRuleList.h
@@ -25,20 +25,30 @@ class CSSRuleList : public Bindings::LegacyPlatformObject {
 public:
     CSSRuleList& impl() { return *this; }
 
-    static CSSRuleList* create(Bindings::WindowObject&, NonnullRefPtrVector<CSSRule>&& rules);
-    CSSRuleList(Bindings::WindowObject&, NonnullRefPtrVector<CSSRule>&&);
+    static CSSRuleList* create(Bindings::WindowObject&, JS::MarkedVector<CSSRule*> const&);
+    static CSSRuleList* create_empty(Bindings::WindowObject&);
+
+    explicit CSSRuleList(Bindings::WindowObject&);
     ~CSSRuleList() = default;
 
-    RefPtr<CSSRule> item(size_t index) const
+    CSSRule const* item(size_t index) const
+    {
+        if (index >= length())
+            return nullptr;
+        return &m_rules[index];
+    }
+
+    CSSRule* item(size_t index)
     {
         if (index >= length())
             return nullptr;
-        return m_rules[index];
+        return &m_rules[index];
     }
+
     size_t length() const { return m_rules.size(); }
 
-    using ConstIterator = AK::SimpleIterator<AK::NonnullPtrVector<NonnullRefPtr<CSSRule>> const, CSSRule const>;
-    using Iterator = AK::SimpleIterator<AK::NonnullPtrVector<NonnullRefPtr<CSSRule>>, CSSRule>;
+    using ConstIterator = AK::SimpleIterator<Vector<CSSRule&> const, CSSRule const>;
+    using Iterator = AK::SimpleIterator<Vector<CSSRule&>, CSSRule>;
 
     ConstIterator const begin() const { return m_rules.begin(); }
     Iterator begin() { return m_rules.begin(); }
@@ -50,19 +60,21 @@ public:
     virtual JS::Value item_value(size_t index) const override;
 
     DOM::ExceptionOr<void> remove_a_css_rule(u32 index);
-    DOM::ExceptionOr<unsigned> insert_a_css_rule(Variant<StringView, NonnullRefPtr<CSSRule>>, u32 index);
+    DOM::ExceptionOr<unsigned> insert_a_css_rule(Variant<StringView, CSSRule*>, u32 index);
 
     void for_each_effective_style_rule(Function<void(CSSStyleRule const&)> const& callback) const;
     // Returns whether the match state of any media queries changed after evaluation.
     bool evaluate_media_queries(HTML::Window const&);
 
 private:
-    NonnullRefPtrVector<CSSRule> m_rules;
+    virtual void visit_edges(Cell::Visitor&) override;
+
+    Vector<CSSRule&> m_rules;
 };
 
 }
 
 namespace Web::Bindings {
-inline JS::Object* wrap(JS::GlobalObject&, Web::CSS::CSSRuleList& object) { return &object; }
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSRuleList& object) { return &object; }
 using CSSRuleListWrapper = Web::CSS::CSSRuleList;
 }
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp
index 9b6a2ad0c2..25757b1636 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.cpp
@@ -4,15 +4,24 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSStyleRulePrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSStyleRule.h>
 #include <LibWeb/CSS/Parser/Parser.h>
 
 namespace Web::CSS {
 
-CSSStyleRule::CSSStyleRule(NonnullRefPtrVector<Selector>&& selectors, NonnullRefPtr<CSSStyleDeclaration>&& declaration)
-    : m_selectors(move(selectors))
+CSSStyleRule* CSSStyleRule::create(Bindings::WindowObject& window_object, NonnullRefPtrVector<Web::CSS::Selector>&& selectors, NonnullRefPtr<Web::CSS::CSSStyleDeclaration>&& declaration)
+{
+    return window_object.heap().allocate<CSSStyleRule>(window_object.realm(), window_object, move(selectors), move(declaration));
+}
+
+CSSStyleRule::CSSStyleRule(Bindings::WindowObject& window_object, NonnullRefPtrVector<Selector>&& selectors, NonnullRefPtr<CSSStyleDeclaration>&& declaration)
+    : CSSRule(window_object)
+    , m_selectors(move(selectors))
     , m_declaration(move(declaration))
 {
+    set_prototype(&window_object.ensure_web_prototype<Bindings::CSSStyleRulePrototype>("CSSStyleRule"));
 }
 
 // https://www.w3.org/TR/cssom/#dom-cssstylerule-style
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h
index 090c15db1f..cff6461137 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.h
@@ -16,23 +16,21 @@
 namespace Web::CSS {
 
 class CSSStyleRule final : public CSSRule {
+    JS_OBJECT(CSSStyleRule, CSSRule);
     AK_MAKE_NONCOPYABLE(CSSStyleRule);
     AK_MAKE_NONMOVABLE(CSSStyleRule);
 
 public:
-    using WrapperType = Bindings::CSSStyleRuleWrapper;
-
-    static NonnullRefPtr<CSSStyleRule> create(NonnullRefPtrVector<Selector>&& selectors, NonnullRefPtr<CSSStyleDeclaration>&& declaration)
-    {
-        return adopt_ref(*new CSSStyleRule(move(selectors), move(declaration)));
-    }
+    static CSSStyleRule* create(Bindings::WindowObject&, NonnullRefPtrVector<Selector>&&, NonnullRefPtr<CSSStyleDeclaration>&&);
+    CSSStyleRule(Bindings::WindowObject&, NonnullRefPtrVector<Selector>&&, NonnullRefPtr<CSSStyleDeclaration>&&);
 
     virtual ~CSSStyleRule() override = default;
 
+    CSSStyleRule& impl() { return *this; }
+
     NonnullRefPtrVector<Selector> const& selectors() const { return m_selectors; }
     CSSStyleDeclaration const& declaration() const { return m_declaration; }
 
-    virtual StringView class_name() const override { return "CSSStyleRule"sv; };
     virtual Type type() const override { return Type::Style; };
 
     String selector_text() const;
@@ -41,8 +39,6 @@ public:
     CSSStyleDeclaration* style();
 
 private:
-    CSSStyleRule(NonnullRefPtrVector<Selector>&&, NonnullRefPtr<CSSStyleDeclaration>&&);
-
     virtual String serialized() const override;
 
     NonnullRefPtrVector<Selector> m_selectors;
@@ -53,3 +49,8 @@ template<>
 inline bool CSSRule::fast_is<CSSStyleRule>() const { return type() == CSSRule::Type::Style; }
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSStyleRule& object) { return &object; }
+using CSSStyleRuleWrapper = Web::CSS::CSSStyleRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.idl b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.idl
index 5e4708a6e6..2d6a8dc214 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleRule.idl
@@ -1,6 +1,7 @@
 #import <CSS/CSSRule.idl>
 #import <CSS/CSSStyleDeclaration.idl>
 
+[Exposed=Window, NoInstanceWrapper]
 interface CSSStyleRule : CSSRule {
 
     attribute CSSOMString selectorText;
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.cpp b/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.cpp
index dd0e33c731..1828e30f62 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.cpp
@@ -13,14 +13,14 @@
 
 namespace Web::CSS {
 
-CSSStyleSheet* CSSStyleSheet::create(Bindings::WindowObject& window_object, NonnullRefPtrVector<CSSRule> rules, Optional<AK::URL> location)
+CSSStyleSheet* CSSStyleSheet::create(Bindings::WindowObject& window_object, CSSRuleList& rules, Optional<AK::URL> location)
 {
-    return window_object.heap().allocate<CSSStyleSheet>(window_object.realm(), window_object, move(rules), move(location));
+    return window_object.heap().allocate<CSSStyleSheet>(window_object.realm(), window_object, rules, move(location));
 }
 
-CSSStyleSheet::CSSStyleSheet(Bindings::WindowObject& window_object, NonnullRefPtrVector<CSSRule> rules, Optional<AK::URL> location)
+CSSStyleSheet::CSSStyleSheet(Bindings::WindowObject& window_object, CSSRuleList& rules, Optional<AK::URL> location)
     : StyleSheet(window_object)
-    , m_rules(CSSRuleList::create(window_object, move(rules)))
+    , m_rules(&rules)
 {
     set_prototype(&window_object.ensure_web_prototype<Bindings::CSSStyleSheetPrototype>("CSSStyleSheet"));
 
@@ -35,6 +35,8 @@ void CSSStyleSheet::visit_edges(Cell::Visitor& visitor)
 {
     Base::visit_edges(visitor);
     visitor.visit(m_style_sheet_list.ptr());
+    visitor.visit(m_rules);
+    visitor.visit(m_owner_css_rule);
 }
 
 // https://www.w3.org/TR/cssom/#dom-cssstylesheet-insertrule
@@ -54,12 +56,11 @@ DOM::ExceptionOr<unsigned> CSSStyleSheet::insert_rule(StringView rule, unsigned
     // FIXME: 5. If parsed rule is an @import rule, and the constructed flag is set, throw a SyntaxError DOMException.
 
     // 6. Return the result of invoking insert a CSS rule rule in the CSS rules at index.
-    auto parsed_rule_nonnull = parsed_rule.release_nonnull();
-    auto result = m_rules->insert_a_css_rule(parsed_rule_nonnull, index);
+    auto result = m_rules->insert_a_css_rule(parsed_rule, index);
 
     if (!result.is_exception()) {
         // NOTE: The spec doesn't say where to set the parent style sheet, so we'll do it here.
-        parsed_rule_nonnull->set_parent_style_sheet(this);
+        parsed_rule->set_parent_style_sheet(this);
 
         if (m_style_sheet_list) {
             m_style_sheet_list->document().style_computer().invalidate_rule_cache();
diff --git a/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.h b/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.h
index 3dd08e1733..7712a13f3f 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSStyleSheet.h
@@ -24,9 +24,9 @@ class CSSStyleSheet final
     JS_OBJECT(CSSStyleSheet, StyleSheet);
 
 public:
-    static CSSStyleSheet* create(Bindings::WindowObject&, NonnullRefPtrVector<CSSRule> rules, Optional<AK::URL> location);
+    static CSSStyleSheet* create(Bindings::WindowObject&, CSSRuleList& rules, Optional<AK::URL> location);
 
-    explicit CSSStyleSheet(Bindings::WindowObject&, NonnullRefPtrVector<CSSRule>, Optional<AK::URL> location);
+    explicit CSSStyleSheet(Bindings::WindowObject&, CSSRuleList&, Optional<AK::URL> location);
     virtual ~CSSStyleSheet() override = default;
 
     CSSStyleSheet& impl() { return *this; }
@@ -57,9 +57,8 @@ private:
 
     CSSRuleList* m_rules { nullptr };
 
-    WeakPtr<CSSRule> m_owner_css_rule;
-
     JS::GCPtr<StyleSheetList> m_style_sheet_list;
+    CSSRule* m_owner_css_rule { nullptr };
 };
 
 }
diff --git a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp
index b00611f32e..602ca34768 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp
+++ b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.cpp
@@ -4,15 +4,23 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibWeb/Bindings/CSSSupportsRulePrototype.h>
+#include <LibWeb/Bindings/WindowObject.h>
 #include <LibWeb/CSS/CSSSupportsRule.h>
 #include <LibWeb/CSS/Parser/Parser.h>
 
 namespace Web::CSS {
 
-CSSSupportsRule::CSSSupportsRule(NonnullRefPtr<Supports>&& supports, NonnullRefPtrVector<CSSRule>&& rules)
-    : CSSConditionRule(move(rules))
+CSSSupportsRule* CSSSupportsRule::create(Bindings::WindowObject& window_object, NonnullRefPtr<Supports>&& supports, CSSRuleList& rules)
+{
+    return window_object.heap().allocate<CSSSupportsRule>(window_object.realm(), window_object, move(supports), rules);
+}
+
+CSSSupportsRule::CSSSupportsRule(Bindings::WindowObject& window_object, NonnullRefPtr<Supports>&& supports, CSSRuleList& rules)
+    : CSSConditionRule(window_object, rules)
     , m_supports(move(supports))
 {
+    set_prototype(&window_object.ensure_web_prototype<Bindings::CSSSupportsRulePrototype>("CSSSupportsRule"));
 }
 
 String CSSSupportsRule::condition_text() const
diff --git a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.h b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.h
index 6bc3b1ea4c..31e0dcac7b 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.h
+++ b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.h
@@ -17,20 +17,18 @@ namespace Web::CSS {
 
 // https://www.w3.org/TR/css-conditional-3/#the-csssupportsrule-interface
 class CSSSupportsRule final : public CSSConditionRule {
+    JS_OBJECT(CSSSupportsRule, CSSConditionRule);
     AK_MAKE_NONCOPYABLE(CSSSupportsRule);
     AK_MAKE_NONMOVABLE(CSSSupportsRule);
 
 public:
-    using WrapperType = Bindings::CSSSupportsRuleWrapper;
-
-    static NonnullRefPtr<CSSSupportsRule> create(NonnullRefPtr<Supports>&& supports, NonnullRefPtrVector<CSSRule>&& rules)
-    {
-        return adopt_ref(*new CSSSupportsRule(move(supports), move(rules)));
-    }
+    static CSSSupportsRule* create(Bindings::WindowObject&, NonnullRefPtr<Supports>&&, CSSRuleList&);
+    explicit CSSSupportsRule(Bindings::WindowObject&, NonnullRefPtr<Supports>&&, CSSRuleList&);
 
     virtual ~CSSSupportsRule() = default;
 
-    virtual StringView class_name() const override { return "CSSSupportsRule"sv; };
+    CSSSupportsRule& impl() { return *this; }
+
     virtual Type type() const override { return Type::Supports; };
 
     String condition_text() const override;
@@ -38,8 +36,6 @@ public:
     virtual bool condition_matches() const override { return m_supports->matches(); }
 
 private:
-    explicit CSSSupportsRule(NonnullRefPtr<Supports>&&, NonnullRefPtrVector<CSSRule>&&);
-
     virtual String serialized() const override;
 
     NonnullRefPtr<Supports> m_supports;
@@ -49,3 +45,8 @@ template<>
 inline bool CSSRule::fast_is<CSSSupportsRule>() const { return type() == CSSRule::Type::Supports; }
 
 }
+
+namespace Web::Bindings {
+inline JS::Object* wrap(JS::Realm&, Web::CSS::CSSSupportsRule& object) { return &object; }
+using CSSSupportsRuleWrapper = Web::CSS::CSSSupportsRule;
+}
diff --git a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.idl b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.idl
index f60b2a2ebf..f4e9fbb89d 100644
--- a/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.idl
+++ b/Userland/Libraries/LibWeb/CSS/CSSSupportsRule.idl
@@ -1,5 +1,5 @@
 #import <CSS/CSSConditionRule.idl>
 
-[Exposed=Window]
+[Exposed=Window, NoInstanceWrapper]
 interface CSSSupportsRule : CSSConditionRule {
 };
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
index 359f58635e..e32ae4efdb 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
+++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.cpp
@@ -44,6 +44,11 @@ ParsingContext::ParsingContext()
 {
 }
 
+ParsingContext::ParsingContext(Bindings::WindowObject& window_object)
+    : m_window_object(window_object)
+{
+}
+
 ParsingContext::ParsingContext(DOM::Document const& document, AK::URL url)
     : m_window_object(document.preferred_window_object())
     , m_document(&document)
@@ -194,15 +199,16 @@ CSSStyleSheet* Parser::parse_as_css_stylesheet(Optional<AK::URL> location)
     auto style_sheet = parse_a_stylesheet(m_token_stream, {});
 
     // Interpret all of the resulting top-level qualified rules as style rules, defined below.
-    NonnullRefPtrVector<CSSRule> rules;
+    JS::MarkedVector<CSSRule*> rules(m_context.window_object().heap());
     for (auto& raw_rule : style_sheet.rules) {
-        auto rule = convert_to_rule(raw_rule);
+        auto* rule = convert_to_rule(raw_rule);
         // If any style rule is invalid, or any at-rule is not recognized or is invalid according to its grammar or context, it’s a parse error. Discard that rule.
         if (rule)
-            rules.append(*rule);
+            rules.append(rule);
     }
 
-    return CSSStyleSheet::create(m_context.window_object(), move(rules), move(location));
+    auto* rule_list = CSSRuleList::create(m_context.window_object(), move(rules));
+    return CSSStyleSheet::create(m_context.window_object(), *rule_list, move(location));
 }
 
 Optional<SelectorList> Parser::parse_as_selector(SelectorParsingMode parsing_mode)
@@ -2096,7 +2102,7 @@ Vector<DeclarationOrAtRule> Parser::consume_a_list_of_declarations(TokenStream<T
     }
 }
 
-RefPtr<CSSRule> Parser::parse_as_css_rule()
+CSSRule* Parser::parse_as_css_rule()
 {
     auto maybe_rule = parse_a_rule(m_token_stream);
     if (maybe_rule)
@@ -2593,7 +2599,7 @@ RefPtr<StyleValue> Parser::parse_linear_gradient_function(ComponentValue const&
     return LinearGradientStyleValue::create(gradient_direction, move(color_stops), gradient_type, repeating_gradient);
 }
 
-RefPtr<CSSRule> Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
+CSSRule* Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
 {
     if (rule->is_at_rule()) {
         if (has_ignored_vendor_prefix(rule->at_rule_name())) {
@@ -2625,8 +2631,7 @@ RefPtr<CSSRule> Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
 
             if (url.has_value())
                 return CSSImportRule::create(url.value(), const_cast<DOM::Document&>(*m_context.document()));
-            else
-                dbgln_if(CSS_PARSER_DEBUG, "Unable to parse url from @import rule");
+            dbgln_if(CSS_PARSER_DEBUG, "Unable to parse url from @import rule");
 
         } else if (rule->at_rule_name().equals_ignoring_case("media"sv)) {
 
@@ -2637,13 +2642,13 @@ RefPtr<CSSRule> Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
 
             auto child_tokens = TokenStream { rule->block()->values() };
             auto parser_rules = parse_a_list_of_rules(child_tokens);
-            NonnullRefPtrVector<CSSRule> child_rules;
+            JS::MarkedVector<CSSRule*> child_rules(m_context.window_object().heap());
             for (auto& raw_rule : parser_rules) {
                 if (auto child_rule = convert_to_rule(raw_rule))
-                    child_rules.append(*child_rule);
+                    child_rules.append(child_rule);
             }
-
-            return CSSMediaRule::create(MediaList::create(move(media_query_list)), move(child_rules));
+            auto* rule_list = CSSRuleList::create(m_context.window_object(), move(child_rules));
+            return CSSMediaRule::create(m_context.window_object(), MediaList::create(move(media_query_list)), *rule_list);
 
         } else if (rule->at_rule_name().equals_ignoring_case("supports"sv)) {
 
@@ -2661,13 +2666,14 @@ RefPtr<CSSRule> Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
                 return {};
             auto child_tokens = TokenStream { rule->block()->values() };
             auto parser_rules = parse_a_list_of_rules(child_tokens);
-            NonnullRefPtrVector<CSSRule> child_rules;
+            JS::MarkedVector<CSSRule*> child_rules(m_context.window_object().heap());
             for (auto& raw_rule : parser_rules) {
                 if (auto child_rule = convert_to_rule(raw_rule))
-                    child_rules.append(*child_rule);
+                    child_rules.append(child_rule);
             }
 
-            return CSSSupportsRule::create(supports.release_nonnull(), move(child_rules));
+            auto* rule_list = CSSRuleList::create(m_context.window_object(), move(child_rules));
+            return CSSSupportsRule::create(m_context.window_object(), supports.release_nonnull(), *rule_list);
 
         } else {
             dbgln_if(CSS_PARSER_DEBUG, "Unrecognized CSS at-rule: @{}", rule->at_rule_name());
@@ -2706,7 +2712,7 @@ RefPtr<CSSRule> Parser::convert_to_rule(NonnullRefPtr<Rule> rule)
             return {};
         }
 
-        return CSSStyleRule::create(move(selectors.value()), move(*declaration));
+        return CSSStyleRule::create(m_context.window_object(), move(selectors.value()), move(*declaration));
     }
 
     return {};
@@ -4690,7 +4696,7 @@ RefPtr<StyleValue> Parser::parse_font_family_value(Vector<ComponentValue> const&
     return StyleValueList::create(move(font_families), StyleValueList::Separator::Comma);
 }
 
-RefPtr<CSSRule> Parser::parse_font_face_rule(TokenStream<ComponentValue>& tokens)
+CSSRule* Parser::parse_font_face_rule(TokenStream<ComponentValue>& tokens)
 {
     auto declarations_and_at_rules = parse_a_list_of_declarations(tokens);
 
@@ -4791,7 +4797,7 @@ RefPtr<CSSRule> Parser::parse_font_face_rule(TokenStream<ComponentValue>& tokens
         unicode_range.empend(0x0u, 0x10FFFFu);
     }
 
-    return CSSFontFaceRule::create(FontFace { font_family.release_value(), move(src), move(unicode_range) });
+    return CSSFontFaceRule::create(m_context.window_object(), FontFace { font_family.release_value(), move(src), move(unicode_range) });
 }
 
 Vector<FontFace::Source> Parser::parse_font_face_src(TokenStream<ComponentValue>& component_values)
@@ -6385,7 +6391,7 @@ namespace Web {
 CSS::CSSStyleSheet* parse_css_stylesheet(CSS::Parser::ParsingContext const& context, StringView css, Optional<AK::URL> location)
 {
     if (css.is_empty())
-        return CSS::CSSStyleSheet::create(context.window_object(), {}, location);
+        return CSS::CSSStyleSheet::create(context.window_object(), *CSS::CSSRuleList::create_empty(context.window_object()), location);
     CSS::Parser::Parser parser(context, css);
     return parser.parse_as_css_stylesheet(location);
 }
@@ -6406,7 +6412,7 @@ RefPtr<CSS::StyleValue> parse_css_value(CSS::Parser::ParsingContext const& conte
     return parser.parse_as_css_value(property_id);
 }
 
-RefPtr<CSS::CSSRule> parse_css_rule(CSS::Parser::ParsingContext const& context, StringView css_text)
+CSS::CSSRule* parse_css_rule(CSS::Parser::ParsingContext const& context, StringView css_text)
 {
     CSS::Parser::Parser parser(context, css_text);
     return parser.parse_as_css_rule();
diff --git a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
index 262814c49b..5779008004 100644
--- a/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
+++ b/Userland/Libraries/LibWeb/CSS/Parser/Parser.h
@@ -35,6 +35,7 @@ namespace Web::CSS::Parser {
 class ParsingContext {
 public:
     ParsingContext();
+    explicit ParsingContext(Bindings::WindowObject&);
     explicit ParsingContext(DOM::Document const&);
     explicit ParsingContext(DOM::Document const&, AK::URL);
     explicit ParsingContext(DOM::ParentNode&);
@@ -127,7 +128,7 @@ public:
 
     CSSStyleSheet* parse_as_css_stylesheet(Optional<AK::URL> location);
     RefPtr<ElementInlineCSSStyleDeclaration> parse_as_style_attribute(DOM::Element&);
-    RefPtr<CSSRule> parse_as_css_rule();
+    CSSRule* parse_as_css_rule();
     Optional<StyleProperty> parse_as_supports_condition();
 
     enum class SelectorParsingMode {
@@ -235,10 +236,10 @@ private:
 
     Optional<GeneralEnclosed> parse_general_enclosed(TokenStream<ComponentValue>&);
 
-    RefPtr<CSSRule> parse_font_face_rule(TokenStream<ComponentValue>&);
+    CSSRule* parse_font_face_rule(TokenStream<ComponentValue>&);
     Vector<FontFace::Source> parse_font_face_src(TokenStream<ComponentValue>&);
 
-    RefPtr<CSSRule> convert_to_rule(NonnullRefPtr<Rule>);
+    CSSRule* convert_to_rule(NonnullRefPtr<Rule>);
     RefPtr<PropertyOwningCSSStyleDeclaration> convert_to_style_declaration(Vector<DeclarationOrAtRule> declarations);
     Optional<StyleProperty> convert_to_style_property(Declaration const&);
 
@@ -423,7 +424,7 @@ CSS::CSSStyleSheet* parse_css_stylesheet(CSS::Parser::ParsingContext const&, Str
 RefPtr<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);
-RefPtr<CSS::CSSRule> parse_css_rule(CSS::Parser::ParsingContext const&, StringView);
+CSS::CSSRule* parse_css_rule(CSS::Parser::ParsingContext const&, StringView);
 RefPtr<CSS::MediaQuery> parse_media_query(CSS::Parser::ParsingContext const&, StringView);
 NonnullRefPtrVector<CSS::MediaQuery> parse_media_query_list(CSS::Parser::ParsingContext const&, StringView);
 RefPtr<CSS::Supports> parse_css_supports(CSS::Parser::ParsingContext const&, StringView);
diff --git a/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp b/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
index ec1c395003..fb484acf06 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
@@ -184,7 +184,7 @@ Vector<MatchingRule> StyleComputer::collect_matching_rules(DOM::Element const& e
             size_t selector_index = 0;
             for (auto& selector : rule.selectors()) {
                 if (SelectorEngine::matches(selector, element, pseudo_element)) {
-                    matching_rules.append({ rule, style_sheet_index, rule_index, selector_index, selector.specificity() });
+                    matching_rules.append({ &rule, style_sheet_index, rule_index, selector_index, selector.specificity() });
                     break;
                 }
                 ++selector_index;
@@ -1264,7 +1264,7 @@ void StyleComputer::build_rule_cache()
         sheet.for_each_effective_style_rule([&](auto const& rule) {
             size_t selector_index = 0;
             for (CSS::Selector const& selector : rule.selectors()) {
-                MatchingRule matching_rule { rule, style_sheet_index, rule_index, selector_index, selector.specificity() };
+                MatchingRule matching_rule { &rule, style_sheet_index, rule_index, selector_index, selector.specificity() };
 
                 bool added_to_bucket = false;
                 for (auto const& simple_selector : selector.compound_selectors().last().simple_selectors) {
diff --git a/Userland/Libraries/LibWeb/CSS/StyleComputer.h b/Userland/Libraries/LibWeb/CSS/StyleComputer.h
index b9cd4993e4..9f2b05fedd 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleComputer.h
+++ b/Userland/Libraries/LibWeb/CSS/StyleComputer.h
@@ -21,7 +21,7 @@
 namespace Web::CSS {
 
 struct MatchingRule {
-    RefPtr<CSSStyleRule> rule;
+    CSSStyleRule const* rule { nullptr };
     size_t style_sheet_index { 0 };
     size_t rule_index { 0 };
     size_t selector_index { 0 };
diff --git a/Userland/Libraries/LibWeb/Forward.h b/Userland/Libraries/LibWeb/Forward.h
index 8e437f2736..f847f72348 100644
--- a/Userland/Libraries/LibWeb/Forward.h
+++ b/Userland/Libraries/LibWeb/Forward.h
@@ -459,15 +459,7 @@ class CharacterDataWrapper;
 class CloseEventWrapper;
 class CommentWrapper;
 class CryptoWrapper;
-class CSSConditionRuleWrapper;
-class CSSFontFaceRuleWrapper;
-class CSSGroupingRuleWrapper;
-class CSSImportRuleWrapper;
-class CSSMediaRuleWrapper;
-class CSSRuleWrapper;
 class CSSStyleDeclarationWrapper;
-class CSSStyleRuleWrapper;
-class CSSSupportsRuleWrapper;
 class CustomEventWrapper;
 class DocumentFragmentWrapper;
 class DocumentTypeWrapper;
diff --git a/Userland/Libraries/LibWeb/idl_files.cmake b/Userland/Libraries/LibWeb/idl_files.cmake
index bb4d5c4444..ac32cd609b 100644
--- a/Userland/Libraries/LibWeb/idl_files.cmake
+++ b/Userland/Libraries/LibWeb/idl_files.cmake
@@ -3,17 +3,17 @@
 
 libweb_js_wrapper(Crypto/Crypto)
 libweb_js_wrapper(Crypto/SubtleCrypto)
-libweb_js_wrapper(CSS/CSSConditionRule)
-libweb_js_wrapper(CSS/CSSFontFaceRule)
-libweb_js_wrapper(CSS/CSSGroupingRule)
-libweb_js_wrapper(CSS/CSSImportRule)
-libweb_js_wrapper(CSS/CSSMediaRule)
-libweb_js_wrapper(CSS/CSSRule)
+libweb_js_wrapper(CSS/CSSConditionRule NO_INSTANCE)
+libweb_js_wrapper(CSS/CSSFontFaceRule NO_INSTANCE)
+libweb_js_wrapper(CSS/CSSGroupingRule NO_INSTANCE)
+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/CSSStyleRule)
+libweb_js_wrapper(CSS/CSSStyleRule NO_INSTANCE)
 libweb_js_wrapper(CSS/CSSStyleSheet NO_INSTANCE)
-libweb_js_wrapper(CSS/CSSSupportsRule)
+libweb_js_wrapper(CSS/CSSSupportsRule NO_INSTANCE)
 libweb_js_wrapper(CSS/MediaList)
 libweb_js_wrapper(CSS/MediaQueryList)
 libweb_js_wrapper(CSS/MediaQueryListEvent)