diff --git a/Libraries/LibWeb/ARIA/ARIAMixin.h b/Libraries/LibWeb/ARIA/ARIAMixin.h
index 1759486c474..de3943dbacd 100644
--- a/Libraries/LibWeb/ARIA/ARIAMixin.h
+++ b/Libraries/LibWeb/ARIA/ARIAMixin.h
@@ -11,6 +11,7 @@
 #include <LibWeb/ARIA/AriaData.h>
 #include <LibWeb/ARIA/AttributeNames.h>
 #include <LibWeb/ARIA/Roles.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::ARIA {
@@ -27,7 +28,7 @@ namespace Web::ARIA {
     __ENUMERATE_ARIA_ATTRIBUTE(aria_labelled_by_elements, aria_labelled_by)     \
     __ENUMERATE_ARIA_ATTRIBUTE(aria_owns_elements, aria_owns)
 
-class ARIAMixin {
+class WEB_API ARIAMixin {
 public:
     virtual ~ARIAMixin();
 
diff --git a/Libraries/LibWeb/ARIA/Roles.h b/Libraries/LibWeb/ARIA/Roles.h
index 8b483d9ceaf..5ebbeffea38 100644
--- a/Libraries/LibWeb/ARIA/Roles.h
+++ b/Libraries/LibWeb/ARIA/Roles.h
@@ -8,6 +8,7 @@
 
 #include <AK/Forward.h>
 #include <AK/StringView.h>
+#include <LibWeb/Export.h>
 
 namespace Web::ARIA {
 
@@ -121,7 +122,7 @@ enum class Role {
 #undef __ENUMERATE_ARIA_ROLE
 };
 
-StringView role_name(Role);
+WEB_API StringView role_name(Role);
 Optional<Role> role_from_string(StringView role_name);
 
 bool is_abstract_role(Role);
diff --git a/Libraries/LibWeb/Animations/Animatable.h b/Libraries/LibWeb/Animations/Animatable.h
index 1efb3446d4c..cf67e7e7fd0 100644
--- a/Libraries/LibWeb/Animations/Animatable.h
+++ b/Libraries/LibWeb/Animations/Animatable.h
@@ -11,6 +11,7 @@
 #include <AK/FlyString.h>
 #include <AK/HashMap.h>
 #include <LibWeb/Animations/KeyframeEffect.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
@@ -33,7 +34,7 @@ struct GetAnimationsOptions {
 };
 
 // https://drafts.csswg.org/web-animations-1/#animatable
-class Animatable {
+class WEB_API Animatable {
 public:
     struct TransitionAttributes {
         double delay;
diff --git a/Libraries/LibWeb/Bindings/Intrinsics.h b/Libraries/LibWeb/Bindings/Intrinsics.h
index 198aae36f3e..03feac28868 100644
--- a/Libraries/LibWeb/Bindings/Intrinsics.h
+++ b/Libraries/LibWeb/Bindings/Intrinsics.h
@@ -13,6 +13,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibJS/Runtime/VM.h>
+#include <LibWeb/Export.h>
 
 #define WEB_SET_PROTOTYPE_FOR_INTERFACE_WITH_CUSTOM_NAME(interface_class, interface_name)                      \
     do {                                                                                                       \
@@ -84,7 +85,7 @@ private:
     GC::Ref<JS::Realm> m_realm;
 };
 
-Intrinsics& host_defined_intrinsics(JS::Realm& realm);
+WEB_API Intrinsics& host_defined_intrinsics(JS::Realm& realm);
 
 template<typename T>
 [[nodiscard]] JS::Object& ensure_web_namespace(JS::Realm& realm, FlyString const& namespace_name)
diff --git a/Libraries/LibWeb/Bindings/MainThreadVM.h b/Libraries/LibWeb/Bindings/MainThreadVM.h
index c082d5eab93..b172688d863 100644
--- a/Libraries/LibWeb/Bindings/MainThreadVM.h
+++ b/Libraries/LibWeb/Bindings/MainThreadVM.h
@@ -13,6 +13,7 @@
 #include <LibWeb/Bindings/AgentType.h>
 #include <LibWeb/DOM/Element.h>
 #include <LibWeb/DOM/MutationObserver.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/EventLoop/EventLoop.h>
 #include <LibWeb/HTML/Scripting/Agent.h>
 
@@ -33,11 +34,11 @@ struct WebEngineCustomJobCallbackData final : public JS::JobCallback::CustomData
 
 HTML::Script* active_script();
 
-void initialize_main_thread_vm(AgentType);
-JS::VM& main_thread_vm();
+WEB_API void initialize_main_thread_vm(AgentType);
+WEB_API JS::VM& main_thread_vm();
 
 void queue_mutation_observer_microtask(DOM::Document const&);
-NonnullOwnPtr<JS::ExecutionContext> create_a_new_javascript_realm(JS::VM&, Function<JS::Object*(JS::Realm&)> create_global_object, Function<JS::Object*(JS::Realm&)> create_global_this_value);
-void invoke_custom_element_reactions(Vector<GC::Root<DOM::Element>>& element_queue);
+WEB_API NonnullOwnPtr<JS::ExecutionContext> create_a_new_javascript_realm(JS::VM&, Function<JS::Object*(JS::Realm&)> create_global_object, Function<JS::Object*(JS::Realm&)> create_global_this_value);
+WEB_API void invoke_custom_element_reactions(Vector<GC::Root<DOM::Element>>& element_queue);
 
 }
diff --git a/Libraries/LibWeb/Bindings/PlatformObject.h b/Libraries/LibWeb/Bindings/PlatformObject.h
index c01b86b60d9..c9bd73af23a 100644
--- a/Libraries/LibWeb/Bindings/PlatformObject.h
+++ b/Libraries/LibWeb/Bindings/PlatformObject.h
@@ -8,6 +8,7 @@
 
 #include <AK/Weakable.h>
 #include <LibJS/Runtime/Object.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Bindings {
@@ -22,7 +23,7 @@ namespace Web::Bindings {
     }
 
 // https://webidl.spec.whatwg.org/#dfn-platform-object
-class PlatformObject : public JS::Object {
+class WEB_API PlatformObject : public JS::Object {
     JS_OBJECT(PlatformObject, JS::Object);
 
 public:
diff --git a/Libraries/LibWeb/CMakeLists.txt b/Libraries/LibWeb/CMakeLists.txt
index b21338cb423..97da4e01559 100644
--- a/Libraries/LibWeb/CMakeLists.txt
+++ b/Libraries/LibWeb/CMakeLists.txt
@@ -1066,7 +1066,7 @@ set(GENERATED_SOURCES
     HTML/Parser/NamedCharacterReferences.cpp
 )
 
-ladybird_lib(LibWeb web)
+ladybird_lib(LibWeb web EXPLICIT_SYMBOL_EXPORT)
 
 target_link_libraries(LibWeb PRIVATE LibCore LibCompress LibCrypto LibJS LibHTTP LibGfx LibIPC LibRegex LibSyntax LibTextCodec LibUnicode LibMedia LibWasm LibXML LibIDL LibURL LibTLS LibRequests LibGC LibThreading skia ${ANGLE_TARGETS})
 
diff --git a/Libraries/LibWeb/CSS/CSS.h b/Libraries/LibWeb/CSS/CSS.h
index 193447aecb4..2c01fb33d6b 100644
--- a/Libraries/LibWeb/CSS/CSS.h
+++ b/Libraries/LibWeb/CSS/CSS.h
@@ -10,6 +10,7 @@
 #include <AK/String.h>
 #include <AK/StringView.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 #include <LibWeb/WebIDL/Types.h>
 
@@ -23,12 +24,12 @@ struct PropertyDefinition {
     Optional<String> initial_value;
 };
 
-WebIDL::ExceptionOr<String> escape(JS::VM&, StringView identifier);
+WEB_API WebIDL::ExceptionOr<String> escape(JS::VM&, StringView identifier);
 
-bool supports(JS::VM&, StringView property, StringView value);
-WebIDL::ExceptionOr<bool> supports(JS::VM&, StringView condition_text);
+WEB_API bool supports(JS::VM&, StringView property, StringView value);
+WEB_API WebIDL::ExceptionOr<bool> supports(JS::VM&, StringView condition_text);
 
-WebIDL::ExceptionOr<void> register_property(JS::VM&, PropertyDefinition definition);
+WEB_API WebIDL::ExceptionOr<void> register_property(JS::VM&, PropertyDefinition definition);
 
 GC::Ref<CSSUnitValue> number(JS::VM&, WebIDL::Double value);
 GC::Ref<CSSUnitValue> percent(JS::VM&, WebIDL::Double value);
diff --git a/Libraries/LibWeb/CSS/CSSImportRule.h b/Libraries/LibWeb/CSS/CSSImportRule.h
index a9f3abb3480..ba3c5a8b986 100644
--- a/Libraries/LibWeb/CSS/CSSImportRule.h
+++ b/Libraries/LibWeb/CSS/CSSImportRule.h
@@ -12,10 +12,11 @@
 #include <LibWeb/CSS/CSSStyleSheet.h>
 #include <LibWeb/CSS/URL.h>
 #include <LibWeb/DOM/DocumentLoadEventDelayer.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
-class CSSImportRule final
+class WEB_API CSSImportRule final
     : public CSSRule {
     WEB_PLATFORM_OBJECT(CSSImportRule, CSSRule);
     GC_DECLARE_ALLOCATOR(CSSImportRule);
diff --git a/Libraries/LibWeb/CSS/CSSRule.h b/Libraries/LibWeb/CSS/CSSRule.h
index 00558307987..1096934d657 100644
--- a/Libraries/LibWeb/CSS/CSSRule.h
+++ b/Libraries/LibWeb/CSS/CSSRule.h
@@ -12,11 +12,12 @@
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/CSS/CSSStyleDeclaration.h>
 #include <LibWeb/CSS/Selector.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/Types.h>
 
 namespace Web::CSS {
 
-class CSSRule : public Bindings::PlatformObject {
+class WEB_API CSSRule : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(CSSRule, Bindings::PlatformObject);
 
 public:
diff --git a/Libraries/LibWeb/CSS/CSSRuleList.h b/Libraries/LibWeb/CSS/CSSRuleList.h
index f2d509c05e9..89b3d2abefd 100644
--- a/Libraries/LibWeb/CSS/CSSRuleList.h
+++ b/Libraries/LibWeb/CSS/CSSRuleList.h
@@ -12,6 +12,7 @@
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/CSS/CSSRule.h>
 #include <LibWeb/CSS/Parser/RuleContext.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/TraversalOrder.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
@@ -19,7 +20,7 @@
 namespace Web::CSS {
 
 // https://www.w3.org/TR/cssom/#the-cssrulelist-interface
-class CSSRuleList : public Bindings::PlatformObject {
+class WEB_API CSSRuleList : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(CSSRuleList, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(CSSRuleList);
 
diff --git a/Libraries/LibWeb/CSS/CSSStyleProperties.h b/Libraries/LibWeb/CSS/CSSStyleProperties.h
index b3ddd4b6878..756b2f49d78 100644
--- a/Libraries/LibWeb/CSS/CSSStyleProperties.h
+++ b/Libraries/LibWeb/CSS/CSSStyleProperties.h
@@ -10,11 +10,12 @@
 #include <LibWeb/CSS/CSSStyleDeclaration.h>
 #include <LibWeb/CSS/GeneratedCSSStyleProperties.h>
 #include <LibWeb/DOM/Node.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
 // https://drafts.csswg.org/cssom/#cssstyleproperties
-class CSSStyleProperties
+class WEB_API CSSStyleProperties
     : public CSSStyleDeclaration
     , public Bindings::GeneratedCSSStyleProperties {
     WEB_PLATFORM_OBJECT(CSSStyleProperties, CSSStyleDeclaration);
diff --git a/Libraries/LibWeb/CSS/CSSStyleSheet.h b/Libraries/LibWeb/CSS/CSSStyleSheet.h
index c6c92596b0b..d8c3b470391 100644
--- a/Libraries/LibWeb/CSS/CSSStyleSheet.h
+++ b/Libraries/LibWeb/CSS/CSSStyleSheet.h
@@ -15,6 +15,7 @@
 #include <LibWeb/CSS/Parser/Parser.h>
 #include <LibWeb/CSS/StyleSheet.h>
 #include <LibWeb/DOM/Node.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/Types.h>
 
 namespace Web::CSS {
@@ -29,7 +30,7 @@ struct CSSStyleSheetInit {
 };
 
 // https://drafts.csswg.org/cssom-1/#cssstylesheet
-class CSSStyleSheet final : public StyleSheet {
+class WEB_API CSSStyleSheet final : public StyleSheet {
     WEB_PLATFORM_OBJECT(CSSStyleSheet, StyleSheet);
     GC_DECLARE_ALLOCATOR(CSSStyleSheet);
 
diff --git a/Libraries/LibWeb/CSS/ComputedProperties.h b/Libraries/LibWeb/CSS/ComputedProperties.h
index 73d4130434f..5e838ab421e 100644
--- a/Libraries/LibWeb/CSS/ComputedProperties.h
+++ b/Libraries/LibWeb/CSS/ComputedProperties.h
@@ -21,10 +21,11 @@
 #include <LibWeb/CSS/PseudoClass.h>
 #include <LibWeb/CSS/PseudoClassBitmap.h>
 #include <LibWeb/CSS/StyleProperty.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
-class ComputedProperties final : public JS::Cell {
+class WEB_API ComputedProperties final : public JS::Cell {
     GC_CELL(ComputedProperties, JS::Cell);
     GC_DECLARE_ALLOCATOR(ComputedProperties);
 
diff --git a/Libraries/LibWeb/CSS/EdgeRect.h b/Libraries/LibWeb/CSS/EdgeRect.h
index 85a8b71ac8a..0437bafc021 100644
--- a/Libraries/LibWeb/CSS/EdgeRect.h
+++ b/Libraries/LibWeb/CSS/EdgeRect.h
@@ -11,10 +11,11 @@
 
 #include <LibGfx/Rect.h>
 #include <LibWeb/CSS/Length.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
-struct EdgeRect {
+struct WEB_API EdgeRect {
     Length top_edge;
     Length right_edge;
     Length bottom_edge;
diff --git a/Libraries/LibWeb/CSS/Length.h b/Libraries/LibWeb/CSS/Length.h
index 56dfdf4905c..7ec690b08b1 100644
--- a/Libraries/LibWeb/CSS/Length.h
+++ b/Libraries/LibWeb/CSS/Length.h
@@ -11,12 +11,13 @@
 #include <LibGfx/Forward.h>
 #include <LibGfx/Rect.h>
 #include <LibWeb/CSS/SerializationMode.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/PixelUnits.h>
 
 namespace Web::CSS {
 
-class Length {
+class WEB_API Length {
 public:
     enum class Type : u8 {
         // Font-relative
diff --git a/Libraries/LibWeb/CSS/Parser/ComponentValue.h b/Libraries/LibWeb/CSS/Parser/ComponentValue.h
index b86c96e80ab..d6128d2b4e9 100644
--- a/Libraries/LibWeb/CSS/Parser/ComponentValue.h
+++ b/Libraries/LibWeb/CSS/Parser/ComponentValue.h
@@ -12,11 +12,12 @@
 #include <AK/RefPtr.h>
 #include <LibWeb/CSS/Parser/Token.h>
 #include <LibWeb/CSS/Parser/Types.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS::Parser {
 
 // https://drafts.csswg.org/css-syntax/#component-value
-class ComponentValue {
+class WEB_API ComponentValue {
     AK_MAKE_DEFAULT_COPYABLE(ComponentValue);
     AK_MAKE_DEFAULT_MOVABLE(ComponentValue);
 
diff --git a/Libraries/LibWeb/CSS/Parser/ErrorReporter.h b/Libraries/LibWeb/CSS/Parser/ErrorReporter.h
index a9a3f27987c..9fcc23165c1 100644
--- a/Libraries/LibWeb/CSS/Parser/ErrorReporter.h
+++ b/Libraries/LibWeb/CSS/Parser/ErrorReporter.h
@@ -9,6 +9,7 @@
 #include <AK/FlyString.h>
 #include <AK/HashMap.h>
 #include <AK/String.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS::Parser {
 
@@ -125,7 +126,7 @@ using ParsingError = Variant<UnknownPropertyError, UnknownRuleError, UnknownMedi
 
 String serialize_parsing_error(ParsingError const&);
 
-class ErrorReporter {
+class WEB_API ErrorReporter {
 public:
     static ErrorReporter& the();
 
diff --git a/Libraries/LibWeb/CSS/Parser/Syntax.h b/Libraries/LibWeb/CSS/Parser/Syntax.h
index 729caeb36a5..6606a3f48ac 100644
--- a/Libraries/LibWeb/CSS/Parser/Syntax.h
+++ b/Libraries/LibWeb/CSS/Parser/Syntax.h
@@ -11,10 +11,11 @@
 #include <AK/OwnPtr.h>
 #include <AK/String.h>
 #include <LibWeb/CSS/PropertyID.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS::Parser {
 
-class SyntaxNode {
+class WEB_API SyntaxNode {
 public:
     enum class NodeType : u8 {
         Universal,
diff --git a/Libraries/LibWeb/CSS/Parser/SyntaxParsing.h b/Libraries/LibWeb/CSS/Parser/SyntaxParsing.h
index ec883462f99..07f8aa12faa 100644
--- a/Libraries/LibWeb/CSS/Parser/SyntaxParsing.h
+++ b/Libraries/LibWeb/CSS/Parser/SyntaxParsing.h
@@ -9,11 +9,12 @@
 #include <AK/OwnPtr.h>
 #include <AK/Vector.h>
 #include <LibWeb/DOM/AbstractElement.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::CSS::Parser {
 
-OwnPtr<SyntaxNode> parse_as_syntax(Vector<ComponentValue> const&);
+WEB_API OwnPtr<SyntaxNode> parse_as_syntax(Vector<ComponentValue> const&);
 
 NonnullRefPtr<StyleValue const> parse_with_a_syntax(ParsingParams const&, Vector<ComponentValue> const& input, SyntaxNode const& syntax, Optional<DOM::AbstractElement> const& element = {});
 
diff --git a/Libraries/LibWeb/CSS/Parser/Token.h b/Libraries/LibWeb/CSS/Parser/Token.h
index de4c59ae39a..fe2bfcca3a8 100644
--- a/Libraries/LibWeb/CSS/Parser/Token.h
+++ b/Libraries/LibWeb/CSS/Parser/Token.h
@@ -9,11 +9,12 @@
 
 #include <AK/FlyString.h>
 #include <LibWeb/CSS/Number.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::CSS::Parser {
 
-class Token {
+class WEB_API Token {
 public:
     enum class Type : u8 {
         Invalid,
diff --git a/Libraries/LibWeb/CSS/Parser/Tokenizer.h b/Libraries/LibWeb/CSS/Parser/Tokenizer.h
index 9682039462d..c238aab6069 100644
--- a/Libraries/LibWeb/CSS/Parser/Tokenizer.h
+++ b/Libraries/LibWeb/CSS/Parser/Tokenizer.h
@@ -12,6 +12,7 @@
 #include <AK/Types.h>
 #include <AK/Utf8View.h>
 #include <LibWeb/CSS/Parser/Token.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::CSS::Parser {
@@ -57,7 +58,7 @@ public:
     u32 third {};
 };
 
-class Tokenizer {
+class WEB_API Tokenizer {
 public:
     static Vector<Token> tokenize(StringView input, StringView encoding);
 
diff --git a/Libraries/LibWeb/CSS/Serialize.h b/Libraries/LibWeb/CSS/Serialize.h
index 56c52900574..3f1352ff950 100644
--- a/Libraries/LibWeb/CSS/Serialize.h
+++ b/Libraries/LibWeb/CSS/Serialize.h
@@ -13,14 +13,15 @@
 #include <LibGfx/Color.h>
 #include <LibGfx/Font/UnicodeRange.h>
 #include <LibWeb/CSS/StyleProperty.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
 void escape_a_character(StringBuilder&, u32 character);
 void escape_a_character_as_code_point(StringBuilder&, u32 character);
-void serialize_an_identifier(StringBuilder&, StringView ident);
+WEB_API void serialize_an_identifier(StringBuilder&, StringView ident);
 void serialize_a_string(StringBuilder&, StringView string);
-void serialize_a_url(StringBuilder&, StringView url);
+WEB_API void serialize_a_url(StringBuilder&, StringView url);
 void serialize_unicode_ranges(StringBuilder&, Vector<Gfx::UnicodeRange> const& unicode_ranges);
 void serialize_a_srgb_value(StringBuilder&, Color color);
 void serialize_a_number(StringBuilder&, double value);
diff --git a/Libraries/LibWeb/CSS/StyleComputer.h b/Libraries/LibWeb/CSS/StyleComputer.h
index 9148c98e7ca..13351705e7f 100644
--- a/Libraries/LibWeb/CSS/StyleComputer.h
+++ b/Libraries/LibWeb/CSS/StyleComputer.h
@@ -20,6 +20,7 @@
 #include <LibWeb/CSS/CascadedProperties.h>
 #include <LibWeb/CSS/Selector.h>
 #include <LibWeb/CSS/StyleInvalidationData.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Loader/ResourceLoader.h>
 
@@ -126,7 +127,7 @@ struct RuleCache {
 
 class FontLoader;
 
-class StyleComputer final : public GC::Cell {
+class WEB_API StyleComputer final : public GC::Cell {
     GC_CELL(StyleComputer, GC::Cell);
     GC_DECLARE_ALLOCATOR(StyleComputer);
 
diff --git a/Libraries/LibWeb/CSS/StyleSheet.h b/Libraries/LibWeb/CSS/StyleSheet.h
index b85d97fc5e5..5b8a5d4bc95 100644
--- a/Libraries/LibWeb/CSS/StyleSheet.h
+++ b/Libraries/LibWeb/CSS/StyleSheet.h
@@ -9,12 +9,13 @@
 
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/CSS/MediaList.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::CSS {
 
 // https://drafts.csswg.org/cssom-1/#the-stylesheet-interface
-class StyleSheet : public Bindings::PlatformObject {
+class WEB_API StyleSheet : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(StyleSheet, Bindings::PlatformObject);
 
 public:
diff --git a/Libraries/LibWeb/CSS/StyleSheetIdentifier.h b/Libraries/LibWeb/CSS/StyleSheetIdentifier.h
index 9351505738f..eb5962b50a0 100644
--- a/Libraries/LibWeb/CSS/StyleSheetIdentifier.h
+++ b/Libraries/LibWeb/CSS/StyleSheetIdentifier.h
@@ -8,6 +8,7 @@
 
 #include <LibIPC/Forward.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::CSS {
@@ -35,9 +36,9 @@ Optional<StyleSheetIdentifier::Type> style_sheet_identifier_type_from_string(Str
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::CSS::StyleSheetIdentifier const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::CSS::StyleSheetIdentifier const&);
 
 template<>
-ErrorOr<Web::CSS::StyleSheetIdentifier> decode(Decoder&);
+WEB_API ErrorOr<Web::CSS::StyleSheetIdentifier> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/CSS/StyleSheetList.h b/Libraries/LibWeb/CSS/StyleSheetList.h
index 6472b0dafa1..050319fde19 100644
--- a/Libraries/LibWeb/CSS/StyleSheetList.h
+++ b/Libraries/LibWeb/CSS/StyleSheetList.h
@@ -10,10 +10,11 @@
 
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/CSS/CSSStyleSheet.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
-class StyleSheetList final : public Bindings::PlatformObject {
+class WEB_API StyleSheetList final : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(StyleSheetList, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(StyleSheetList);
 
diff --git a/Libraries/LibWeb/CSS/StyleValues/DisplayStyleValue.h b/Libraries/LibWeb/CSS/StyleValues/DisplayStyleValue.h
index d87fcc26ed3..edbd4f32912 100644
--- a/Libraries/LibWeb/CSS/StyleValues/DisplayStyleValue.h
+++ b/Libraries/LibWeb/CSS/StyleValues/DisplayStyleValue.h
@@ -8,10 +8,11 @@
 
 #include <LibWeb/CSS/Display.h>
 #include <LibWeb/CSS/StyleValues/StyleValue.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
-class DisplayStyleValue : public StyleValueWithDefaultOperators<DisplayStyleValue> {
+class WEB_API DisplayStyleValue : public StyleValueWithDefaultOperators<DisplayStyleValue> {
 public:
     static ValueComparingNonnullRefPtr<DisplayStyleValue const> create(Display const&);
     virtual ~DisplayStyleValue() override = default;
diff --git a/Libraries/LibWeb/CSS/StyleValues/EasingStyleValue.h b/Libraries/LibWeb/CSS/StyleValues/EasingStyleValue.h
index 30468d78446..24929ceea81 100644
--- a/Libraries/LibWeb/CSS/StyleValues/EasingStyleValue.h
+++ b/Libraries/LibWeb/CSS/StyleValues/EasingStyleValue.h
@@ -12,6 +12,7 @@
 
 #include <LibWeb/CSS/CalculatedOr.h>
 #include <LibWeb/CSS/StyleValues/StyleValue.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
@@ -88,7 +89,7 @@ public:
         String to_string(SerializationMode) const;
     };
 
-    struct Function : public Variant<Linear, CubicBezier, Steps> {
+    struct WEB_API Function : public Variant<Linear, CubicBezier, Steps> {
         using Variant::Variant;
 
         double evaluate_at(double input_progress, bool before_flag) const;
diff --git a/Libraries/LibWeb/CSS/StyleValues/LengthStyleValue.h b/Libraries/LibWeb/CSS/StyleValues/LengthStyleValue.h
index 926fcdcadcc..5439f494d08 100644
--- a/Libraries/LibWeb/CSS/StyleValues/LengthStyleValue.h
+++ b/Libraries/LibWeb/CSS/StyleValues/LengthStyleValue.h
@@ -11,10 +11,11 @@
 
 #include <LibWeb/CSS/Length.h>
 #include <LibWeb/CSS/StyleValues/DimensionStyleValue.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
-class LengthStyleValue final : public DimensionStyleValue {
+class WEB_API LengthStyleValue final : public DimensionStyleValue {
 public:
     static ValueComparingNonnullRefPtr<LengthStyleValue const> create(Length const&);
     virtual ~LengthStyleValue() override = default;
diff --git a/Libraries/LibWeb/CSS/StyleValues/StyleValue.h b/Libraries/LibWeb/CSS/StyleValues/StyleValue.h
index 930062d659a..263d6262b83 100644
--- a/Libraries/LibWeb/CSS/StyleValues/StyleValue.h
+++ b/Libraries/LibWeb/CSS/StyleValues/StyleValue.h
@@ -25,6 +25,7 @@
 #include <LibWeb/CSS/Length.h>
 #include <LibWeb/CSS/PreferredColorScheme.h>
 #include <LibWeb/CSS/SerializationMode.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::CSS {
@@ -153,7 +154,7 @@ struct ColorResolutionContext {
     [[nodiscard]] static ColorResolutionContext for_layout_node_with_style(Layout::NodeWithStyle const&);
 };
 
-class StyleValue : public RefCounted<StyleValue> {
+class WEB_API StyleValue : public RefCounted<StyleValue> {
 public:
     virtual ~StyleValue() = default;
 
diff --git a/Libraries/LibWeb/CSS/Supports.h b/Libraries/LibWeb/CSS/Supports.h
index 1f19f09e2b9..8081204a381 100644
--- a/Libraries/LibWeb/CSS/Supports.h
+++ b/Libraries/LibWeb/CSS/Supports.h
@@ -11,11 +11,12 @@
 #include <AK/RefCounted.h>
 #include <AK/String.h>
 #include <LibWeb/CSS/BooleanExpression.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
 // https://www.w3.org/TR/css-conditional-3/#at-supports
-class Supports final : public RefCounted<Supports> {
+class WEB_API Supports final : public RefCounted<Supports> {
 public:
     class Declaration final : public BooleanExpression {
     public:
diff --git a/Libraries/LibWeb/CSS/SyntaxHighlighter/SyntaxHighlighter.h b/Libraries/LibWeb/CSS/SyntaxHighlighter/SyntaxHighlighter.h
index 040067f639e..40a01355028 100644
--- a/Libraries/LibWeb/CSS/SyntaxHighlighter/SyntaxHighlighter.h
+++ b/Libraries/LibWeb/CSS/SyntaxHighlighter/SyntaxHighlighter.h
@@ -7,10 +7,11 @@
 #pragma once
 
 #include <LibSyntax/Highlighter.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
-class SyntaxHighlighter : public Syntax::Highlighter {
+class WEB_API SyntaxHighlighter : public Syntax::Highlighter {
 public:
     SyntaxHighlighter() = default;
     virtual ~SyntaxHighlighter() override = default;
diff --git a/Libraries/LibWeb/CSS/SystemColor.h b/Libraries/LibWeb/CSS/SystemColor.h
index fe70c1300b1..7db65f896e2 100644
--- a/Libraries/LibWeb/CSS/SystemColor.h
+++ b/Libraries/LibWeb/CSS/SystemColor.h
@@ -8,6 +8,7 @@
 
 #include <LibGfx/Color.h>
 #include <LibWeb/CSS/PreferredColorScheme.h>
+#include <LibWeb/Export.h>
 
 // https://www.w3.org/TR/css-color-4/#css-system-colors
 namespace Web::CSS::SystemColor {
@@ -23,8 +24,8 @@ Color canvas_text(PreferredColorScheme);
 Color field(PreferredColorScheme);
 Color field_text(PreferredColorScheme);
 Color gray_text(PreferredColorScheme);
-Color highlight(PreferredColorScheme);
-Color highlight_text(PreferredColorScheme);
+WEB_API Color highlight(PreferredColorScheme);
+WEB_API Color highlight_text(PreferredColorScheme);
 Color link_text(PreferredColorScheme);
 Color mark(PreferredColorScheme);
 Color mark_text(PreferredColorScheme);
diff --git a/Libraries/LibWeb/CSS/Transformation.h b/Libraries/LibWeb/CSS/Transformation.h
index eb38fe61fb1..4de6cacc902 100644
--- a/Libraries/LibWeb/CSS/Transformation.h
+++ b/Libraries/LibWeb/CSS/Transformation.h
@@ -12,12 +12,13 @@
 #include <LibWeb/CSS/Length.h>
 #include <LibWeb/CSS/PercentageOr.h>
 #include <LibWeb/CSS/TransformFunctions.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
 using TransformValue = Variant<AngleOrCalculated, LengthPercentage, NumberPercentage>;
 
-class Transformation {
+class WEB_API Transformation {
 public:
     Transformation(TransformFunction function, Vector<TransformValue>&& values);
 
diff --git a/Libraries/LibWeb/CSS/URL.h b/Libraries/LibWeb/CSS/URL.h
index 8e2f67ee2b6..44dbc33d945 100644
--- a/Libraries/LibWeb/CSS/URL.h
+++ b/Libraries/LibWeb/CSS/URL.h
@@ -11,6 +11,7 @@
 #include <AK/Vector.h>
 #include <LibGC/Ptr.h>
 #include <LibWeb/CSS/Enums.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
@@ -42,7 +43,7 @@ private:
 };
 
 // https://drafts.csswg.org/css-values-4/#urls
-class URL {
+class WEB_API URL {
 public:
     enum class Type : u8 {
         Url,
diff --git a/Libraries/LibWeb/Clipboard/SystemClipboard.h b/Libraries/LibWeb/Clipboard/SystemClipboard.h
index 4182e919cca..5bc5248f9be 100644
--- a/Libraries/LibWeb/Clipboard/SystemClipboard.h
+++ b/Libraries/LibWeb/Clipboard/SystemClipboard.h
@@ -10,6 +10,7 @@
 #include <AK/String.h>
 #include <AK/Vector.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Clipboard {
 
@@ -29,15 +30,15 @@ struct SystemClipboardItem {
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::Clipboard::SystemClipboardRepresentation const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::Clipboard::SystemClipboardRepresentation const&);
 
 template<>
-ErrorOr<Web::Clipboard::SystemClipboardRepresentation> decode(Decoder&);
+WEB_API ErrorOr<Web::Clipboard::SystemClipboardRepresentation> decode(Decoder&);
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::Clipboard::SystemClipboardItem const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::Clipboard::SystemClipboardItem const&);
 
 template<>
-ErrorOr<Web::Clipboard::SystemClipboardItem> decode(Decoder&);
+WEB_API ErrorOr<Web::Clipboard::SystemClipboardItem> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/Cookie/Cookie.h b/Libraries/LibWeb/Cookie/Cookie.h
index 0ba2539b06e..71c5998b3cd 100644
--- a/Libraries/LibWeb/Cookie/Cookie.h
+++ b/Libraries/LibWeb/Cookie/Cookie.h
@@ -10,6 +10,7 @@
 #include <AK/Time.h>
 #include <LibIPC/Forward.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Cookie {
 
@@ -25,7 +26,7 @@ enum class Source {
     Http,
 };
 
-struct Cookie {
+struct WEB_API Cookie {
     String creation_time_to_string() const;
     String last_access_time_to_string() const;
     String expiry_time_to_string() const;
@@ -44,20 +45,20 @@ struct Cookie {
     bool persistent { false };
 };
 
-StringView same_site_to_string(SameSite same_site_mode);
-SameSite same_site_from_string(StringView same_site_mode);
+WEB_API StringView same_site_to_string(SameSite same_site_mode);
+WEB_API SameSite same_site_from_string(StringView same_site_mode);
 
-Optional<String> canonicalize_domain(const URL::URL& url);
-bool path_matches(StringView request_path, StringView cookie_path);
+WEB_API Optional<String> canonicalize_domain(const URL::URL& url);
+WEB_API bool path_matches(StringView request_path, StringView cookie_path);
 
 }
 
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::Cookie::Cookie const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::Cookie::Cookie const&);
 
 template<>
-ErrorOr<Web::Cookie::Cookie> decode(Decoder&);
+WEB_API ErrorOr<Web::Cookie::Cookie> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/Cookie/ParsedCookie.h b/Libraries/LibWeb/Cookie/ParsedCookie.h
index c1f8f869ff3..5f24d65430c 100644
--- a/Libraries/LibWeb/Cookie/ParsedCookie.h
+++ b/Libraries/LibWeb/Cookie/ParsedCookie.h
@@ -12,6 +12,7 @@
 #include <LibIPC/Forward.h>
 #include <LibURL/Forward.h>
 #include <LibWeb/Cookie/Cookie.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Cookie {
 
@@ -28,18 +29,18 @@ struct ParsedCookie {
 };
 
 Optional<ParsedCookie> parse_cookie(URL::URL const&, StringView cookie_string);
-bool cookie_contains_invalid_control_character(StringView);
-bool domain_matches(StringView string, StringView domain_string);
-String default_path(URL::URL const&);
+WEB_API bool cookie_contains_invalid_control_character(StringView);
+WEB_API bool domain_matches(StringView string, StringView domain_string);
+WEB_API String default_path(URL::URL const&);
 
 }
 
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::Cookie::ParsedCookie const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::Cookie::ParsedCookie const&);
 
 template<>
-ErrorOr<Web::Cookie::ParsedCookie> decode(Decoder&);
+WEB_API ErrorOr<Web::Cookie::ParsedCookie> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/CookieStore/CookieStore.h b/Libraries/LibWeb/CookieStore/CookieStore.h
index de6c2b75514..1f0bbf9a42e 100644
--- a/Libraries/LibWeb/CookieStore/CookieStore.h
+++ b/Libraries/LibWeb/CookieStore/CookieStore.h
@@ -10,6 +10,7 @@
 #include <AK/String.h>
 #include <LibWeb/Bindings/CookieStorePrototype.h>
 #include <LibWeb/DOM/EventTarget.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HighResolutionTime/DOMHighResTimeStamp.h>
 
 namespace Web::CookieStore {
@@ -46,7 +47,7 @@ struct CookieStoreDeleteOptions {
 };
 
 // https://cookiestore.spec.whatwg.org/#cookiestore
-class CookieStore final : public DOM::EventTarget {
+class WEB_API CookieStore final : public DOM::EventTarget {
     WEB_PLATFORM_OBJECT(CookieStore, DOM::EventTarget);
     GC_DECLARE_ALLOCATOR(CookieStore);
 
diff --git a/Libraries/LibWeb/Crypto/Crypto.h b/Libraries/LibWeb/Crypto/Crypto.h
index a400ceae4a2..0834d46cc77 100644
--- a/Libraries/LibWeb/Crypto/Crypto.h
+++ b/Libraries/LibWeb/Crypto/Crypto.h
@@ -8,6 +8,7 @@
 
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/Crypto/SubtleCrypto.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::Crypto {
@@ -36,6 +37,6 @@ private:
     GC::Ptr<SubtleCrypto> m_subtle;
 };
 
-ErrorOr<String> generate_random_uuid();
+WEB_API ErrorOr<String> generate_random_uuid();
 
 }
diff --git a/Libraries/LibWeb/DOM/AdoptedStyleSheets.h b/Libraries/LibWeb/DOM/AdoptedStyleSheets.h
index 8015eb69c53..541ec36ea88 100644
--- a/Libraries/LibWeb/DOM/AdoptedStyleSheets.h
+++ b/Libraries/LibWeb/DOM/AdoptedStyleSheets.h
@@ -6,11 +6,12 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebIDL/ObservableArray.h>
 
 namespace Web::DOM {
 
-GC::Ref<WebIDL::ObservableArray> create_adopted_style_sheets_list(Node& document_or_shadow_root);
+WEB_API GC::Ref<WebIDL::ObservableArray> create_adopted_style_sheets_list(Node& document_or_shadow_root);
 
 }
diff --git a/Libraries/LibWeb/DOM/Attr.h b/Libraries/LibWeb/DOM/Attr.h
index 4afc4943e90..b537e3e4aaf 100644
--- a/Libraries/LibWeb/DOM/Attr.h
+++ b/Libraries/LibWeb/DOM/Attr.h
@@ -9,11 +9,12 @@
 #include <AK/WeakPtr.h>
 #include <LibWeb/DOM/Node.h>
 #include <LibWeb/DOM/QualifiedName.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
 // https://dom.spec.whatwg.org/#attr
-class Attr final : public Node {
+class WEB_API Attr final : public Node {
     WEB_PLATFORM_OBJECT(Attr, Node);
     GC_DECLARE_ALLOCATOR(Attr);
 
diff --git a/Libraries/LibWeb/DOM/CharacterData.h b/Libraries/LibWeb/DOM/CharacterData.h
index 37978634d4c..bfeee5ae7de 100644
--- a/Libraries/LibWeb/DOM/CharacterData.h
+++ b/Libraries/LibWeb/DOM/CharacterData.h
@@ -12,11 +12,12 @@
 #include <LibWeb/DOM/ChildNode.h>
 #include <LibWeb/DOM/Node.h>
 #include <LibWeb/DOM/NonDocumentTypeChildNode.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
 // https://dom.spec.whatwg.org/#characterdata
-class CharacterData
+class WEB_API CharacterData
     : public Node
     , public ChildNode<CharacterData>
     , public NonDocumentTypeChildNode<CharacterData> {
diff --git a/Libraries/LibWeb/DOM/CustomEvent.h b/Libraries/LibWeb/DOM/CustomEvent.h
index b6be322f6ad..74e60e05e51 100644
--- a/Libraries/LibWeb/DOM/CustomEvent.h
+++ b/Libraries/LibWeb/DOM/CustomEvent.h
@@ -9,6 +9,7 @@
 
 #include <AK/FlyString.h>
 #include <LibWeb/DOM/Event.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
@@ -17,7 +18,7 @@ struct CustomEventInit : public EventInit {
 };
 
 // https://dom.spec.whatwg.org/#customevent
-class CustomEvent : public Event {
+class WEB_API CustomEvent : public Event {
     WEB_PLATFORM_OBJECT(CustomEvent, Event);
     GC_DECLARE_ALLOCATOR(CustomEvent);
 
diff --git a/Libraries/LibWeb/DOM/Document.h b/Libraries/LibWeb/DOM/Document.h
index ad6a8b17016..d7824f6b369 100644
--- a/Libraries/LibWeb/DOM/Document.h
+++ b/Libraries/LibWeb/DOM/Document.h
@@ -28,6 +28,7 @@
 #include <LibWeb/Cookie/Cookie.h>
 #include <LibWeb/DOM/ParentNode.h>
 #include <LibWeb/DOM/ShadowRoot.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/BrowsingContext.h>
 #include <LibWeb/HTML/CrossOrigin/OpenerPolicy.h>
 #include <LibWeb/HTML/DocumentReadyState.h>
@@ -161,7 +162,7 @@ enum class PolicyControlledFeature : u8 {
     FocusWithoutUserActivation,
 };
 
-class Document
+class WEB_API Document
     : public ParentNode
     , public HTML::GlobalEventHandlers {
     WEB_PLATFORM_OBJECT(Document, ParentNode);
diff --git a/Libraries/LibWeb/DOM/DocumentFragment.h b/Libraries/LibWeb/DOM/DocumentFragment.h
index 4ba3f269cfd..0a4bfac531e 100644
--- a/Libraries/LibWeb/DOM/DocumentFragment.h
+++ b/Libraries/LibWeb/DOM/DocumentFragment.h
@@ -8,10 +8,11 @@
 
 #include <LibWeb/DOM/Element.h>
 #include <LibWeb/DOM/ParentNode.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
-class DocumentFragment
+class WEB_API DocumentFragment
     : public ParentNode {
     WEB_PLATFORM_OBJECT(DocumentFragment, ParentNode);
     GC_DECLARE_ALLOCATOR(DocumentFragment);
diff --git a/Libraries/LibWeb/DOM/DocumentObserver.h b/Libraries/LibWeb/DOM/DocumentObserver.h
index 32187d08e3d..74e3e83938d 100644
--- a/Libraries/LibWeb/DOM/DocumentObserver.h
+++ b/Libraries/LibWeb/DOM/DocumentObserver.h
@@ -9,13 +9,14 @@
 #include <LibGC/Function.h>
 #include <LibJS/Forward.h>
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/DocumentReadyState.h>
 #include <LibWeb/HTML/VisibilityState.h>
 
 namespace Web::DOM {
 
-class DocumentObserver final : public Bindings::PlatformObject {
+class WEB_API DocumentObserver final : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(DocumentObserver, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(DocumentObserver);
 
diff --git a/Libraries/LibWeb/DOM/Element.h b/Libraries/LibWeb/DOM/Element.h
index 323571c4101..377731ca104 100644
--- a/Libraries/LibWeb/DOM/Element.h
+++ b/Libraries/LibWeb/DOM/Element.h
@@ -26,6 +26,7 @@
 #include <LibWeb/DOM/PseudoElement.h>
 #include <LibWeb/DOM/QualifiedName.h>
 #include <LibWeb/DOM/Slottable.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/AttributeNames.h>
 #include <LibWeb/HTML/EventLoop/Task.h>
 #include <LibWeb/HTML/LazyLoadingElement.h>
@@ -100,7 +101,7 @@ enum class ProximityToTheViewport {
     NotDetermined,
 };
 
-class Element
+class WEB_API Element
     : public ParentNode
     , public ChildNode<Element>
     , public NonDocumentTypeChildNode<Element>
diff --git a/Libraries/LibWeb/DOM/ElementFactory.h b/Libraries/LibWeb/DOM/ElementFactory.h
index a615caba95b..808b6464c4f 100644
--- a/Libraries/LibWeb/DOM/ElementFactory.h
+++ b/Libraries/LibWeb/DOM/ElementFactory.h
@@ -8,13 +8,14 @@
 
 #include <AK/FixedArray.h>
 #include <LibWeb/DOM/Element.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
-ErrorOr<FixedArray<FlyString>> valid_local_names_for_given_html_element_interface(StringView html_element_interface_name);
+WEB_API ErrorOr<FixedArray<FlyString>> valid_local_names_for_given_html_element_interface(StringView html_element_interface_name);
 bool is_unknown_html_element(FlyString const& tag_name);
 
 // FIXME: The spec doesn't say what the default value of synchronous_custom_elements_flag should be.
-WebIDL::ExceptionOr<GC::Ref<Element>> create_element(Document&, FlyString local_name, Optional<FlyString> namespace_, Optional<FlyString> prefix = {}, Optional<String> is = Optional<String> {}, bool synchronous_custom_elements_flag = false);
+WEB_API WebIDL::ExceptionOr<GC::Ref<Element>> create_element(Document&, FlyString local_name, Optional<FlyString> namespace_, Optional<FlyString> prefix = {}, Optional<String> is = Optional<String> {}, bool synchronous_custom_elements_flag = false);
 
 }
diff --git a/Libraries/LibWeb/DOM/Event.h b/Libraries/LibWeb/DOM/Event.h
index 60a16076e88..3559de4e154 100644
--- a/Libraries/LibWeb/DOM/Event.h
+++ b/Libraries/LibWeb/DOM/Event.h
@@ -9,6 +9,7 @@
 #include <AK/FlyString.h>
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/DOM/EventTarget.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HighResolutionTime/DOMHighResTimeStamp.h>
 
 namespace Web::DOM {
@@ -19,7 +20,7 @@ struct EventInit {
     bool composed { false };
 };
 
-class Event : public Bindings::PlatformObject {
+class WEB_API Event : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(Event, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(Event);
 
diff --git a/Libraries/LibWeb/DOM/EventTarget.h b/Libraries/LibWeb/DOM/EventTarget.h
index b7ab5fcb21d..5793d8d423c 100644
--- a/Libraries/LibWeb/DOM/EventTarget.h
+++ b/Libraries/LibWeb/DOM/EventTarget.h
@@ -11,13 +11,14 @@
 #include <LibJS/Forward.h>
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/DOM/DOMEventListener.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/EventHandler.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::DOM {
 
-class EventTarget : public Bindings::PlatformObject {
+class WEB_API EventTarget : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(EventTarget, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(EventTarget);
 
diff --git a/Libraries/LibWeb/DOM/MutationType.h b/Libraries/LibWeb/DOM/MutationType.h
index 23f0b8c62a3..993cd748f76 100644
--- a/Libraries/LibWeb/DOM/MutationType.h
+++ b/Libraries/LibWeb/DOM/MutationType.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/FlyString.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM::MutationType {
 
@@ -15,7 +16,7 @@ namespace Web::DOM::MutationType {
     __ENUMERATE_MUTATION_TYPE(characterData) \
     __ENUMERATE_MUTATION_TYPE(childList)
 
-#define __ENUMERATE_MUTATION_TYPE(name) extern FlyString name;
+#define __ENUMERATE_MUTATION_TYPE(name) extern WEB_API FlyString name;
 ENUMERATE_MUTATION_TYPES
 #undef __ENUMERATE_MUTATION_TYPE
 
diff --git a/Libraries/LibWeb/DOM/NamedNodeMap.h b/Libraries/LibWeb/DOM/NamedNodeMap.h
index bf59c3a13db..739edbfe727 100644
--- a/Libraries/LibWeb/DOM/NamedNodeMap.h
+++ b/Libraries/LibWeb/DOM/NamedNodeMap.h
@@ -10,13 +10,14 @@
 #pragma once
 
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::DOM {
 
 // https://dom.spec.whatwg.org/#interface-namednodemap
-class NamedNodeMap : public Bindings::PlatformObject {
+class WEB_API NamedNodeMap : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(NamedNodeMap, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(NamedNodeMap);
 
diff --git a/Libraries/LibWeb/DOM/Node.h b/Libraries/LibWeb/DOM/Node.h
index a83bbef4838..77cdf44863f 100644
--- a/Libraries/LibWeb/DOM/Node.h
+++ b/Libraries/LibWeb/DOM/Node.h
@@ -17,6 +17,7 @@
 #include <LibWeb/DOM/EventTarget.h>
 #include <LibWeb/DOM/NodeType.h>
 #include <LibWeb/DOM/Slottable.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/XMLSerializer.h>
 #include <LibWeb/TraversalDecision.h>
 #include <LibWeb/TreeNode.h>
@@ -138,7 +139,7 @@ enum class SetNeedsLayoutTreeUpdateReason {
 
 [[nodiscard]] StringView to_string(SetNeedsLayoutTreeUpdateReason);
 
-class Node : public EventTarget
+class WEB_API Node : public EventTarget
     , public TreeNode<Node> {
     WEB_PLATFORM_OBJECT(Node, EventTarget);
 
diff --git a/Libraries/LibWeb/DOM/NodeList.h b/Libraries/LibWeb/DOM/NodeList.h
index 5d5409e5e69..06f710c8281 100644
--- a/Libraries/LibWeb/DOM/NodeList.h
+++ b/Libraries/LibWeb/DOM/NodeList.h
@@ -8,11 +8,12 @@
 #pragma once
 
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
 // https://dom.spec.whatwg.org/#nodelist
-class NodeList : public Bindings::PlatformObject {
+class WEB_API NodeList : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(NodeList, Bindings::PlatformObject);
 
 public:
diff --git a/Libraries/LibWeb/DOM/ParentNode.h b/Libraries/LibWeb/DOM/ParentNode.h
index 6d44751e96a..3dd8a48a624 100644
--- a/Libraries/LibWeb/DOM/ParentNode.h
+++ b/Libraries/LibWeb/DOM/ParentNode.h
@@ -7,10 +7,11 @@
 #pragma once
 
 #include <LibWeb/DOM/Node.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
-class ParentNode : public Node {
+class WEB_API ParentNode : public Node {
     WEB_PLATFORM_OBJECT(ParentNode, Node);
     GC_DECLARE_ALLOCATOR(ParentNode);
 
diff --git a/Libraries/LibWeb/DOM/PseudoElement.h b/Libraries/LibWeb/DOM/PseudoElement.h
index 9e977e47a0e..18383fb2cd4 100644
--- a/Libraries/LibWeb/DOM/PseudoElement.h
+++ b/Libraries/LibWeb/DOM/PseudoElement.h
@@ -10,13 +10,14 @@
 #include <LibGC/CellAllocator.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibWeb/CSS/StyleProperty.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/PixelUnits.h>
 #include <LibWeb/TreeNode.h>
 
 namespace Web::DOM {
 
-class PseudoElement : public JS::Cell {
+class WEB_API PseudoElement : public JS::Cell {
     GC_CELL(PseudoElement, JS::Cell);
     GC_DECLARE_ALLOCATOR(PseudoElement);
 
diff --git a/Libraries/LibWeb/DOM/QualifiedName.h b/Libraries/LibWeb/DOM/QualifiedName.h
index b933eec1383..1a064745435 100644
--- a/Libraries/LibWeb/DOM/QualifiedName.h
+++ b/Libraries/LibWeb/DOM/QualifiedName.h
@@ -10,10 +10,11 @@
 
 #include <AK/FlyString.h>
 #include <AK/Optional.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
-class QualifiedName {
+class WEB_API QualifiedName {
 public:
     QualifiedName(FlyString const& local_name, Optional<FlyString> const& prefix, Optional<FlyString> const& namespace_);
 
@@ -25,7 +26,7 @@ public:
 
     FlyString const& as_string() const { return m_impl->as_string; }
 
-    struct Impl : public RefCounted<Impl> {
+    struct WEB_API Impl : public RefCounted<Impl> {
         Impl(FlyString const& local_name, Optional<FlyString> const& prefix, Optional<FlyString> const& namespace_);
         ~Impl();
 
diff --git a/Libraries/LibWeb/DOM/Range.h b/Libraries/LibWeb/DOM/Range.h
index 4c6d85161f8..8114346e6ec 100644
--- a/Libraries/LibWeb/DOM/Range.h
+++ b/Libraries/LibWeb/DOM/Range.h
@@ -11,6 +11,7 @@
 
 #include <LibWeb/DOM/AbstractRange.h>
 #include <LibWeb/DOM/Node.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Selection/Selection.h>
 #include <LibWeb/WebIDL/Types.h>
 
@@ -25,7 +26,7 @@ enum class RelativeBoundaryPointPosition {
 // https://dom.spec.whatwg.org/#concept-range-bp-position
 RelativeBoundaryPointPosition position_of_boundary_point_relative_to_other_boundary_point(BoundaryPoint a, BoundaryPoint b);
 
-class Range final : public AbstractRange {
+class WEB_API Range final : public AbstractRange {
     WEB_PLATFORM_OBJECT(Range, AbstractRange);
     GC_DECLARE_ALLOCATOR(Range);
 
diff --git a/Libraries/LibWeb/DOM/ShadowRoot.h b/Libraries/LibWeb/DOM/ShadowRoot.h
index c2cda672d3a..472f8d5eeda 100644
--- a/Libraries/LibWeb/DOM/ShadowRoot.h
+++ b/Libraries/LibWeb/DOM/ShadowRoot.h
@@ -9,11 +9,12 @@
 #include <LibWeb/Bindings/ShadowRootPrototype.h>
 #include <LibWeb/DOM/DocumentFragment.h>
 #include <LibWeb/DOM/ElementByIdMap.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ObservableArray.h>
 
 namespace Web::DOM {
 
-class ShadowRoot final : public DocumentFragment {
+class WEB_API ShadowRoot final : public DocumentFragment {
     WEB_PLATFORM_OBJECT(ShadowRoot, DocumentFragment);
     GC_DECLARE_ALLOCATOR(ShadowRoot);
 
diff --git a/Libraries/LibWeb/DOM/Slottable.h b/Libraries/LibWeb/DOM/Slottable.h
index e538752740e..5fc9ae6ff3e 100644
--- a/Libraries/LibWeb/DOM/Slottable.h
+++ b/Libraries/LibWeb/DOM/Slottable.h
@@ -10,6 +10,7 @@
 #include <AK/Variant.h>
 #include <LibGC/Ptr.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::DOM {
@@ -18,7 +19,7 @@ namespace Web::DOM {
 using Slottable = Variant<GC::Ref<Element>, GC::Ref<Text>>;
 
 // https://dom.spec.whatwg.org/#mixin-slotable
-class SlottableMixin {
+class WEB_API SlottableMixin {
 public:
     virtual ~SlottableMixin();
 
diff --git a/Libraries/LibWeb/DOM/Text.h b/Libraries/LibWeb/DOM/Text.h
index 2bd7ab719f3..8988d608803 100644
--- a/Libraries/LibWeb/DOM/Text.h
+++ b/Libraries/LibWeb/DOM/Text.h
@@ -10,10 +10,11 @@
 #include <LibWeb/DOM/CharacterData.h>
 #include <LibWeb/DOM/Element.h>
 #include <LibWeb/DOM/Slottable.h>
+#include <LibWeb/Export.h>
 
 namespace Web::DOM {
 
-class Text
+class WEB_API Text
     : public CharacterData
     , public SlottableMixin {
     WEB_PLATFORM_OBJECT(Text, CharacterData);
diff --git a/Libraries/LibWeb/DOMURL/DOMURL.h b/Libraries/LibWeb/DOMURL/DOMURL.h
index 922db2459a7..e4de67145c4 100644
--- a/Libraries/LibWeb/DOMURL/DOMURL.h
+++ b/Libraries/LibWeb/DOMURL/DOMURL.h
@@ -12,6 +12,7 @@
 #include <LibURL/URL.h>
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/DOMURL/URLSearchParams.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/FileAPI/BlobURLStore.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
@@ -93,6 +94,6 @@ private:
 };
 
 // https://url.spec.whatwg.org/#concept-url-parser
-Optional<URL::URL> parse(StringView input, Optional<URL::URL const&> base_url = {}, Optional<StringView> encoding = {});
+WEB_API Optional<URL::URL> parse(StringView input, Optional<URL::URL const&> base_url = {}, Optional<StringView> encoding = {});
 
 }
diff --git a/Libraries/LibWeb/Dump.h b/Libraries/LibWeb/Dump.h
index 0b6306b55b8..bff059fbc5c 100644
--- a/Libraries/LibWeb/Dump.h
+++ b/Libraries/LibWeb/Dump.h
@@ -8,19 +8,20 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web {
 
-void dump_tree(HTML::TraversableNavigable&);
+WEB_API void dump_tree(HTML::TraversableNavigable&);
 void dump_tree(StringBuilder&, DOM::Node const&);
-void dump_tree(DOM::Node const&);
-void dump_tree(StringBuilder&, Layout::Node const&, bool show_box_model = false, bool show_cascaded_properties = false, bool colorize = false);
-void dump_tree(Layout::Node const&, bool show_box_model = true, bool show_cascaded_properties = false);
-void dump_tree(StringBuilder&, Painting::Paintable const&, bool colorize = false, int indent = 0);
-void dump_tree(Painting::Paintable const&);
+WEB_API void dump_tree(DOM::Node const&);
+WEB_API void dump_tree(StringBuilder&, Layout::Node const&, bool show_box_model = false, bool show_cascaded_properties = false, bool colorize = false);
+WEB_API void dump_tree(Layout::Node const&, bool show_box_model = true, bool show_cascaded_properties = false);
+WEB_API void dump_tree(StringBuilder&, Painting::Paintable const&, bool colorize = false, int indent = 0);
+WEB_API void dump_tree(Painting::Paintable const&);
 void dump_sheet(StringBuilder&, CSS::StyleSheet const&);
-void dump_sheet(CSS::StyleSheet const&);
+WEB_API void dump_sheet(CSS::StyleSheet const&);
 void dump_rule(StringBuilder&, CSS::CSSRule const&, int indent_levels = 0);
 void dump_rule(CSS::CSSRule const&);
 void dump_style_properties(StringBuilder&, CSS::CSSStyleProperties const&, int indent_levels = 0);
diff --git a/Libraries/LibWeb/Fetch/BodyInit.h b/Libraries/LibWeb/Fetch/BodyInit.h
index aaec167b981..e31c94c3bf7 100644
--- a/Libraries/LibWeb/Fetch/BodyInit.h
+++ b/Libraries/LibWeb/Fetch/BodyInit.h
@@ -9,6 +9,7 @@
 #include <AK/Forward.h>
 #include <AK/Variant.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Fetch {
@@ -17,7 +18,7 @@ namespace Web::Fetch {
 using BodyInit = Variant<GC::Root<Streams::ReadableStream>, GC::Root<FileAPI::Blob>, GC::Root<WebIDL::BufferSource>, GC::Root<XHR::FormData>, GC::Root<DOMURL::URLSearchParams>, String>;
 
 using BodyInitOrReadableBytes = Variant<GC::Root<Streams::ReadableStream>, GC::Root<FileAPI::Blob>, GC::Root<WebIDL::BufferSource>, GC::Root<XHR::FormData>, GC::Root<DOMURL::URLSearchParams>, String, ReadonlyBytes>;
-Infrastructure::BodyWithType safely_extract_body(JS::Realm&, BodyInitOrReadableBytes const&);
-WebIDL::ExceptionOr<Infrastructure::BodyWithType> extract_body(JS::Realm&, BodyInitOrReadableBytes const&, bool keepalive = false);
+WEB_API Infrastructure::BodyWithType safely_extract_body(JS::Realm&, BodyInitOrReadableBytes const&);
+WEB_API WebIDL::ExceptionOr<Infrastructure::BodyWithType> extract_body(JS::Realm&, BodyInitOrReadableBytes const&, bool keepalive = false);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Enums.h b/Libraries/LibWeb/Fetch/Enums.h
index bb4f6022f43..8d70cc0d7a4 100644
--- a/Libraries/LibWeb/Fetch/Enums.h
+++ b/Libraries/LibWeb/Fetch/Enums.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Requests.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Responses.h>
 #include <LibWeb/Forward.h>
@@ -15,7 +16,7 @@ namespace Web::Fetch {
 
 [[nodiscard]] ReferrerPolicy::ReferrerPolicy from_bindings_enum(Bindings::ReferrerPolicy);
 [[nodiscard]] Infrastructure::Request::Mode from_bindings_enum(Bindings::RequestMode);
-[[nodiscard]] Infrastructure::Request::CredentialsMode from_bindings_enum(Bindings::RequestCredentials);
+[[nodiscard]] WEB_API Infrastructure::Request::CredentialsMode from_bindings_enum(Bindings::RequestCredentials);
 [[nodiscard]] Infrastructure::Request::CacheMode from_bindings_enum(Bindings::RequestCache);
 [[nodiscard]] Infrastructure::Request::RedirectMode from_bindings_enum(Bindings::RequestRedirect);
 [[nodiscard]] Infrastructure::Request::Priority from_bindings_enum(Bindings::RequestPriority);
diff --git a/Libraries/LibWeb/Fetch/Fetching/Fetching.h b/Libraries/LibWeb/Fetch/Fetching/Fetching.h
index f6033799f18..0d5164ffae2 100644
--- a/Libraries/LibWeb/Fetch/Fetching/Fetching.h
+++ b/Libraries/LibWeb/Fetch/Fetching/Fetching.h
@@ -10,6 +10,7 @@
 #include <AK/Forward.h>
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Fetch::Fetching {
@@ -38,7 +39,7 @@ constexpr auto keepalive_maximum_size = 64 * KiB;
 ENUMERATE_BOOL_PARAMS
 #undef __ENUMERATE_BOOL_PARAM
 
-WebIDL::ExceptionOr<GC::Ref<Infrastructure::FetchController>> fetch(JS::Realm&, Infrastructure::Request&, Infrastructure::FetchAlgorithms const&, UseParallelQueue use_parallel_queue = UseParallelQueue::No);
+WEB_API WebIDL::ExceptionOr<GC::Ref<Infrastructure::FetchController>> fetch(JS::Realm&, Infrastructure::Request&, Infrastructure::FetchAlgorithms const&, UseParallelQueue use_parallel_queue = UseParallelQueue::No);
 WebIDL::ExceptionOr<GC::Ptr<PendingResponse>> main_fetch(JS::Realm&, Infrastructure::FetchParams const&, Recursive recursive = Recursive::No);
 void populate_request_from_client(JS::Realm const&, Infrastructure::Request&);
 void fetch_response_handover(JS::Realm&, Infrastructure::FetchParams const&, Infrastructure::Response&);
@@ -54,6 +55,6 @@ void set_sec_fetch_site_header(Infrastructure::Request&);
 void set_sec_fetch_user_header(Infrastructure::Request&);
 void append_fetch_metadata_headers_for_request(Infrastructure::Request&);
 
-void set_http_cache_enabled(bool enabled);
+WEB_API void set_http_cache_enabled(bool enabled);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/FetchAlgorithms.h b/Libraries/LibWeb/Fetch/Infrastructure/FetchAlgorithms.h
index 9c69125cb41..75a4b869c89 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/FetchAlgorithms.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/FetchAlgorithms.h
@@ -10,12 +10,13 @@
 #include <LibGC/Function.h>
 #include <LibGC/Ptr.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#fetch-elsewhere-fetch
-class FetchAlgorithms : public JS::Cell {
+class WEB_API FetchAlgorithms : public JS::Cell {
     GC_CELL(FetchAlgorithms, JS::Cell);
     GC_DECLARE_ALLOCATOR(FetchAlgorithms);
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/FetchController.h b/Libraries/LibWeb/Fetch/Infrastructure/FetchController.h
index 80680098965..740d7f6990b 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/FetchController.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/FetchController.h
@@ -13,6 +13,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibJS/Runtime/VM.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/FetchTimingInfo.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/EventLoop/Task.h>
@@ -21,7 +22,7 @@
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#fetch-controller
-class FetchController : public JS::Cell {
+class WEB_API FetchController : public JS::Cell {
     GC_CELL(FetchController, JS::Cell);
     GC_DECLARE_ALLOCATOR(FetchController);
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/FetchParams.h b/Libraries/LibWeb/Fetch/Infrastructure/FetchParams.h
index 705277dece8..48f8f9e1061 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/FetchParams.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/FetchParams.h
@@ -10,6 +10,7 @@
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/FetchAlgorithms.h>
 #include <LibWeb/Fetch/Infrastructure/FetchController.h>
 #include <LibWeb/Fetch/Infrastructure/FetchTimingInfo.h>
@@ -19,7 +20,7 @@
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#fetch-params
-class FetchParams : public JS::Cell {
+class WEB_API FetchParams : public JS::Cell {
     GC_CELL(FetchParams, JS::Cell);
     GC_DECLARE_ALLOCATOR(FetchParams);
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/FetchRecord.h b/Libraries/LibWeb/Fetch/Infrastructure/FetchRecord.h
index 14beca2a8d5..bfdf2171fe4 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/FetchRecord.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/FetchRecord.h
@@ -6,12 +6,13 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/FetchController.h>
 
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#concept-fetch-record
-class FetchRecord final : public JS::Cell {
+class WEB_API FetchRecord final : public JS::Cell {
     GC_CELL(FetchRecord, JS::Cell);
     GC_DECLARE_ALLOCATOR(FetchRecord);
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/FetchTimingInfo.h b/Libraries/LibWeb/Fetch/Infrastructure/FetchTimingInfo.h
index c135d49d00d..031e62180a6 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/FetchTimingInfo.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/FetchTimingInfo.h
@@ -13,6 +13,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibRequests/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/ConnectionTimingInfo.h>
 #include <LibWeb/HTML/Scripting/SerializedEnvironmentSettingsObject.h>
 #include <LibWeb/HighResolutionTime/DOMHighResTimeStamp.h>
@@ -20,7 +21,7 @@
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#fetch-timing-info
-class FetchTimingInfo : public JS::Cell {
+class WEB_API FetchTimingInfo : public JS::Cell {
     GC_CELL(FetchTimingInfo, JS::Cell);
     GC_DECLARE_ALLOCATOR(FetchTimingInfo);
 
@@ -132,6 +133,6 @@ private:
     bool m_render_blocking { false };
 };
 
-GC::Ref<FetchTimingInfo> create_opaque_timing_info(JS::VM&, FetchTimingInfo const& timing_info);
+WEB_API GC::Ref<FetchTimingInfo> create_opaque_timing_info(JS::VM&, FetchTimingInfo const& timing_info);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/HTTP.h b/Libraries/LibWeb/Fetch/Infrastructure/HTTP.h
index 9a2af944b51..1b145613c8b 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/HTTP.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/HTTP.h
@@ -9,6 +9,7 @@
 
 #include <AK/Forward.h>
 #include <AK/StringView.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Fetch::Infrastructure {
 
@@ -53,6 +54,6 @@ enum class RedirectTaint {
     CrossSite,
 };
 
-[[nodiscard]] String collect_an_http_quoted_string(GenericLexer& lexer, HttpQuotedStringExtractValue extract_value = HttpQuotedStringExtractValue::No);
+[[nodiscard]] WEB_API String collect_an_http_quoted_string(GenericLexer& lexer, HttpQuotedStringExtractValue extract_value = HttpQuotedStringExtractValue::No);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Bodies.h b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Bodies.h
index 5f6fff2e388..737efb605c5 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Bodies.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Bodies.h
@@ -13,6 +13,7 @@
 #include <AK/Variant.h>
 #include <LibGC/Ptr.h>
 #include <LibGC/Root.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/Task.h>
 #include <LibWeb/FileAPI/Blob.h>
 #include <LibWeb/Streams/ReadableStream.h>
@@ -21,7 +22,7 @@
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#concept-body
-class Body final : public JS::Cell {
+class WEB_API Body final : public JS::Cell {
     GC_CELL(Body, JS::Cell);
     GC_DECLARE_ALLOCATOR(Body);
 
@@ -76,6 +77,6 @@ struct BodyWithType {
     Optional<ByteBuffer> type;
 };
 
-GC::Ref<Body> byte_sequence_as_body(JS::Realm&, ReadonlyBytes);
+WEB_API GC::Ref<Body> byte_sequence_as_body(JS::Realm&, ReadonlyBytes);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Headers.h b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Headers.h
index 7dc9a6c5082..d28bb28e2ed 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Headers.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Headers.h
@@ -17,13 +17,14 @@
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/MimeSniff/MimeType.h>
 
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#concept-header
 // A header is a tuple that consists of a name (a header name) and value (a header value).
-struct Header {
+struct WEB_API Header {
     ByteBuffer name;
     ByteBuffer value;
 
@@ -34,7 +35,7 @@ struct Header {
 
 // https://fetch.spec.whatwg.org/#concept-header-list
 // A header list is a list of zero or more headers. It is initially the empty list.
-class HeaderList final
+class WEB_API HeaderList final
     : public JS::Cell
     , public Vector<Header> {
     GC_CELL(HeaderList, JS::Cell);
@@ -75,7 +76,7 @@ struct RangeHeaderValue {
 struct ExtractHeaderParseFailure {
 };
 
-[[nodiscard]] StringView legacy_extract_an_encoding(Optional<MimeSniff::MimeType> const& mime_type, StringView fallback_encoding);
+[[nodiscard]] WEB_API StringView legacy_extract_an_encoding(Optional<MimeSniff::MimeType> const& mime_type, StringView fallback_encoding);
 [[nodiscard]] Optional<Vector<String>> get_decode_and_split_header_value(ReadonlyBytes);
 [[nodiscard]] OrderedHashTable<ByteBuffer> convert_header_names_to_a_sorted_lowercase_set(Span<ReadonlyBytes>);
 [[nodiscard]] bool is_header_name(ReadonlyBytes);
@@ -83,8 +84,8 @@ struct ExtractHeaderParseFailure {
 [[nodiscard]] ByteBuffer normalize_header_value(ReadonlyBytes);
 [[nodiscard]] bool is_cors_safelisted_request_header(Header const&);
 [[nodiscard]] bool is_cors_unsafe_request_header_byte(u8);
-[[nodiscard]] OrderedHashTable<ByteBuffer> get_cors_unsafe_header_names(HeaderList const&);
-[[nodiscard]] bool is_cors_non_wildcard_request_header_name(ReadonlyBytes);
+[[nodiscard]] WEB_API OrderedHashTable<ByteBuffer> get_cors_unsafe_header_names(HeaderList const&);
+[[nodiscard]] WEB_API bool is_cors_non_wildcard_request_header_name(ReadonlyBytes);
 [[nodiscard]] bool is_privileged_no_cors_request_header_name(ReadonlyBytes);
 [[nodiscard]] bool is_cors_safelisted_response_header_name(ReadonlyBytes, Span<ReadonlyBytes>);
 [[nodiscard]] bool is_no_cors_safelisted_request_header_name(ReadonlyBytes);
@@ -93,9 +94,9 @@ struct ExtractHeaderParseFailure {
 [[nodiscard]] bool is_forbidden_response_header_name(ReadonlyBytes);
 [[nodiscard]] bool is_request_body_header_name(ReadonlyBytes);
 [[nodiscard]] Optional<Vector<ByteBuffer>> extract_header_values(Header const&);
-[[nodiscard]] Variant<Vector<ByteBuffer>, ExtractHeaderParseFailure, Empty> extract_header_list_values(ReadonlyBytes, HeaderList const&);
-[[nodiscard]] ByteString build_content_range(u64 const& range_start, u64 const& range_end, u64 const& full_length);
-[[nodiscard]] Optional<RangeHeaderValue> parse_single_range_header_value(ReadonlyBytes, bool);
-[[nodiscard]] ByteBuffer default_user_agent_value();
+[[nodiscard]] WEB_API Variant<Vector<ByteBuffer>, ExtractHeaderParseFailure, Empty> extract_header_list_values(ReadonlyBytes, HeaderList const&);
+[[nodiscard]] WEB_API ByteString build_content_range(u64 const& range_start, u64 const& range_end, u64 const& full_length);
+[[nodiscard]] WEB_API Optional<RangeHeaderValue> parse_single_range_header_value(ReadonlyBytes, bool);
+[[nodiscard]] WEB_API ByteBuffer default_user_agent_value();
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Methods.h b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Methods.h
index a98fdca80c2..0d6ad2b42a3 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Methods.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Methods.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Fetch::Infrastructure {
 
 [[nodiscard]] bool is_method(ReadonlyBytes);
-[[nodiscard]] bool is_cors_safelisted_method(ReadonlyBytes);
+[[nodiscard]] WEB_API bool is_cors_safelisted_method(ReadonlyBytes);
 [[nodiscard]] bool is_forbidden_method(ReadonlyBytes);
 [[nodiscard]] ByteBuffer normalize_method(ReadonlyBytes);
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Requests.h b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Requests.h
index 0a83a4d1410..6ef48a7e5bf 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Requests.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Requests.h
@@ -19,6 +19,7 @@
 #include <LibJS/Heap/Cell.h>
 #include <LibURL/Origin.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Bodies.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Headers.h>
@@ -26,7 +27,7 @@
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#concept-request
-class Request final : public JS::Cell {
+class WEB_API Request final : public JS::Cell {
     GC_CELL(Request, JS::Cell);
     GC_DECLARE_ALLOCATOR(Request);
 
@@ -535,9 +536,9 @@ private:
     BufferPolicy m_buffer_policy { BufferPolicy::BufferResponse };
 };
 
-StringView request_destination_to_string(Request::Destination);
-StringView request_mode_to_string(Request::Mode);
-FlyString initiator_type_to_string(Request::InitiatorType);
+WEB_API StringView request_destination_to_string(Request::Destination);
+WEB_API StringView request_mode_to_string(Request::Mode);
+WEB_API FlyString initiator_type_to_string(Request::InitiatorType);
 
 Optional<Request::Priority> request_priority_from_string(StringView);
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Responses.h b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Responses.h
index cc818f7d359..e4cea041fef 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Responses.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Responses.h
@@ -16,6 +16,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Bodies.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Headers.h>
@@ -24,7 +25,7 @@
 namespace Web::Fetch::Infrastructure {
 
 // https://fetch.spec.whatwg.org/#concept-response
-class Response : public JS::Cell {
+class WEB_API Response : public JS::Cell {
     GC_CELL(Response, JS::Cell);
     GC_DECLARE_ALLOCATOR(Response);
 
@@ -267,7 +268,7 @@ private:
 };
 
 // https://fetch.spec.whatwg.org/#concept-filtered-response-basic
-class BasicFilteredResponse final : public FilteredResponse {
+class WEB_API BasicFilteredResponse final : public FilteredResponse {
     GC_CELL(BasicFilteredResponse, FilteredResponse);
     GC_DECLARE_ALLOCATOR(BasicFilteredResponse);
 
@@ -286,7 +287,7 @@ private:
 };
 
 // https://fetch.spec.whatwg.org/#concept-filtered-response-cors
-class CORSFilteredResponse final : public FilteredResponse {
+class WEB_API CORSFilteredResponse final : public FilteredResponse {
     GC_CELL(CORSFilteredResponse, FilteredResponse);
     GC_DECLARE_ALLOCATOR(CORSFilteredResponse);
 
@@ -305,7 +306,7 @@ private:
 };
 
 // https://fetch.spec.whatwg.org/#concept-filtered-response-opaque
-class OpaqueFilteredResponse final : public FilteredResponse {
+class WEB_API OpaqueFilteredResponse final : public FilteredResponse {
     GC_CELL(OpaqueFilteredResponse, FilteredResponse);
     GC_DECLARE_ALLOCATOR(OpaqueFilteredResponse);
 
@@ -330,7 +331,7 @@ private:
 };
 
 // https://fetch.spec.whatwg.org/#concept-filtered-response-opaque-redirect
-class OpaqueRedirectFilteredResponse final : public FilteredResponse {
+class WEB_API OpaqueRedirectFilteredResponse final : public FilteredResponse {
     GC_CELL(OpaqueRedirectFilteredResponse, FilteredResponse);
     GC_DECLARE_ALLOCATOR(OpaqueRedirectFilteredResponse);
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Statuses.h b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Statuses.h
index 22ea181628d..877a6e2dea8 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Statuses.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/HTTP/Statuses.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Fetch::Infrastructure {
 
@@ -14,8 +15,8 @@ namespace Web::Fetch::Infrastructure {
 // A status is an integer in the range 0 to 999, inclusive.
 using Status = u16;
 
-[[nodiscard]] bool is_null_body_status(Status);
-[[nodiscard]] bool is_ok_status(Status);
-[[nodiscard]] bool is_redirect_status(Status);
+[[nodiscard]] WEB_API bool is_null_body_status(Status);
+[[nodiscard]] WEB_API bool is_ok_status(Status);
+[[nodiscard]] WEB_API bool is_redirect_status(Status);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/MimeTypeBlocking.h b/Libraries/LibWeb/Fetch/Infrastructure/MimeTypeBlocking.h
index df8ac3a3f33..e0a5a69ab76 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/MimeTypeBlocking.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/MimeTypeBlocking.h
@@ -6,11 +6,12 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/RequestOrResponseBlocking.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Fetch::Infrastructure {
 
-[[nodiscard]] RequestOrResponseBlocking should_response_to_request_be_blocked_due_to_its_mime_type(Response const&, Request const&);
+[[nodiscard]] WEB_API RequestOrResponseBlocking should_response_to_request_be_blocked_due_to_its_mime_type(Response const&, Request const&);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/NetworkPartitionKey.h b/Libraries/LibWeb/Fetch/Infrastructure/NetworkPartitionKey.h
index c334b525f64..577a4d009ce 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/NetworkPartitionKey.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/NetworkPartitionKey.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <LibURL/Origin.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Fetch::Infrastructure {
@@ -23,7 +24,7 @@ struct NetworkPartitionKey {
 
 NetworkPartitionKey determine_the_network_partition_key(HTML::Environment const& environment);
 
-Optional<NetworkPartitionKey> determine_the_network_partition_key(Infrastructure::Request const& request);
+WEB_API Optional<NetworkPartitionKey> determine_the_network_partition_key(Infrastructure::Request const& request);
 
 }
 
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/NoSniffBlocking.h b/Libraries/LibWeb/Fetch/Infrastructure/NoSniffBlocking.h
index b703ca76446..d51c5ca1b98 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/NoSniffBlocking.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/NoSniffBlocking.h
@@ -7,12 +7,13 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/RequestOrResponseBlocking.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Fetch::Infrastructure {
 
 [[nodiscard]] bool determine_nosniff(HeaderList const&);
-[[nodiscard]] RequestOrResponseBlocking should_response_to_request_be_blocked_due_to_nosniff(Response const&, Request const&);
+[[nodiscard]] WEB_API RequestOrResponseBlocking should_response_to_request_be_blocked_due_to_nosniff(Response const&, Request const&);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/PortBlocking.h b/Libraries/LibWeb/Fetch/Infrastructure/PortBlocking.h
index c91bdd43ed2..9a361da4653 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/PortBlocking.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/PortBlocking.h
@@ -7,12 +7,13 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/RequestOrResponseBlocking.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Fetch::Infrastructure {
 
-[[nodiscard]] RequestOrResponseBlocking block_bad_port(Request const&);
+[[nodiscard]] WEB_API RequestOrResponseBlocking block_bad_port(Request const&);
 [[nodiscard]] bool is_bad_port(u16);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/Task.h b/Libraries/LibWeb/Fetch/Infrastructure/Task.h
index d2b6385e6e5..1254a0ecbb5 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/Task.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/Task.h
@@ -9,6 +9,7 @@
 #include <AK/Variant.h>
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/EventLoop/Task.h>
 
@@ -17,6 +18,6 @@ namespace Web::Fetch::Infrastructure {
 using TaskDestination = Variant<Empty, GC::Ref<JS::Object>, NonnullRefPtr<HTML::ParallelQueue>>;
 
 HTML::TaskID queue_fetch_task(TaskDestination, GC::Ref<GC::Function<void()>>);
-HTML::TaskID queue_fetch_task(GC::Ref<FetchController>, TaskDestination, GC::Ref<GC::Function<void()>>);
+WEB_API HTML::TaskID queue_fetch_task(GC::Ref<FetchController>, TaskDestination, GC::Ref<GC::Function<void()>>);
 
 }
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/URL.cpp b/Libraries/LibWeb/Fetch/Infrastructure/URL.cpp
index 998f8133a4e..762e63e3599 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/URL.cpp
+++ b/Libraries/LibWeb/Fetch/Infrastructure/URL.cpp
@@ -8,6 +8,7 @@
 
 #include <AK/Base64.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/URL.h>
 #include <LibWeb/Infra/Strings.h>
 #include <LibWeb/MimeSniff/MimeType.h>
diff --git a/Libraries/LibWeb/Fetch/Infrastructure/URL.h b/Libraries/LibWeb/Fetch/Infrastructure/URL.h
index a99b5afc0b3..33ba3d60b81 100644
--- a/Libraries/LibWeb/Fetch/Infrastructure/URL.h
+++ b/Libraries/LibWeb/Fetch/Infrastructure/URL.h
@@ -13,6 +13,7 @@
 #include <AK/String.h>
 #include <AK/StringView.h>
 #include <LibURL/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/MimeSniff/MimeType.h>
 
 namespace Web::Fetch::Infrastructure {
@@ -44,9 +45,9 @@ struct DataURL {
     ByteBuffer body;
 };
 
-[[nodiscard]] bool is_local_url(URL::URL const&);
+[[nodiscard]] WEB_API bool is_local_url(URL::URL const&);
 [[nodiscard]] bool is_fetch_scheme(StringView);
-[[nodiscard]] bool is_http_or_https_scheme(StringView);
-ErrorOr<DataURL> process_data_url(URL::URL const&);
+[[nodiscard]] WEB_API bool is_http_or_https_scheme(StringView);
+WEB_API ErrorOr<DataURL> process_data_url(URL::URL const&);
 
 }
diff --git a/Libraries/LibWeb/FileAPI/Blob.h b/Libraries/LibWeb/FileAPI/Blob.h
index 12d93f75b71..8d90718e194 100644
--- a/Libraries/LibWeb/FileAPI/Blob.h
+++ b/Libraries/LibWeb/FileAPI/Blob.h
@@ -11,6 +11,7 @@
 #include <LibWeb/Bindings/BlobPrototype.h>
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/Bindings/Serializable.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
@@ -27,7 +28,7 @@ struct BlobPropertyBag {
 [[nodiscard]] ErrorOr<ByteBuffer> process_blob_parts(Vector<BlobPart> const& blob_parts, Optional<BlobPropertyBag> const& options = {});
 [[nodiscard]] bool is_basic_latin(StringView view);
 
-class Blob
+class WEB_API Blob
     : public Bindings::PlatformObject
     , public Bindings::Serializable {
     WEB_PLATFORM_OBJECT(Blob, Bindings::PlatformObject);
diff --git a/Libraries/LibWeb/FileAPI/BlobURLStore.h b/Libraries/LibWeb/FileAPI/BlobURLStore.h
index 25ab68ea596..a19f076a609 100644
--- a/Libraries/LibWeb/FileAPI/BlobURLStore.h
+++ b/Libraries/LibWeb/FileAPI/BlobURLStore.h
@@ -31,7 +31,7 @@ ErrorOr<Utf16String> generate_new_blob_url();
 ErrorOr<Utf16String> add_entry_to_blob_url_store(BlobURLEntry::Object);
 bool check_for_same_partition_blob_url_usage(URL::BlobURLEntry const&, GC::Ref<HTML::Environment>);
 struct NavigationEnvironment { };
-Optional<URL::BlobURLEntry::Object> obtain_a_blob_object(URL::BlobURLEntry const&, Variant<GC::Ref<HTML::Environment>, NavigationEnvironment> environment);
+WEB_API Optional<URL::BlobURLEntry::Object> obtain_a_blob_object(URL::BlobURLEntry const&, Variant<GC::Ref<HTML::Environment>, NavigationEnvironment> environment);
 void remove_entry_from_blob_url_store(URL::URL const& url);
 Optional<BlobURLEntry const&> resolve_a_blob_url(URL::URL const&);
 
diff --git a/Libraries/LibWeb/FileAPI/FileList.h b/Libraries/LibWeb/FileAPI/FileList.h
index 62df237d7f8..e502cbbd83b 100644
--- a/Libraries/LibWeb/FileAPI/FileList.h
+++ b/Libraries/LibWeb/FileAPI/FileList.h
@@ -10,12 +10,13 @@
 #include <AK/Vector.h>
 #include <LibGC/Ptr.h>
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/FileAPI/File.h>
 #include <LibWeb/WebIDL/Types.h>
 
 namespace Web::FileAPI {
 
-class FileList
+class WEB_API FileList
     : public Bindings::PlatformObject
     , public Bindings::Serializable {
     WEB_PLATFORM_OBJECT(FileList, Bindings::PlatformObject);
diff --git a/Libraries/LibWeb/Forward.h b/Libraries/LibWeb/Forward.h
index ec421f2f239..598fccc0715 100644
--- a/Libraries/LibWeb/Forward.h
+++ b/Libraries/LibWeb/Forward.h
@@ -12,6 +12,7 @@
 #include <LibGfx/Forward.h>
 #include <LibIPC/Forward.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web {
 
@@ -1220,10 +1221,10 @@ struct FormDataEntry;
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::UniqueNodeID const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::UniqueNodeID const&);
 
 template<>
-ErrorOr<Web::UniqueNodeID> decode(Decoder&);
+WEB_API ErrorOr<Web::UniqueNodeID> decode(Decoder&);
 
 }
 
diff --git a/Libraries/LibWeb/Geometry/DOMPoint.h b/Libraries/LibWeb/Geometry/DOMPoint.h
index af6cbe8be4b..dd2325030c4 100644
--- a/Libraries/LibWeb/Geometry/DOMPoint.h
+++ b/Libraries/LibWeb/Geometry/DOMPoint.h
@@ -7,12 +7,13 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Geometry/DOMPointReadOnly.h>
 
 namespace Web::Geometry {
 
 // https://drafts.fxtf.org/geometry/#DOMPoint
-class DOMPoint final : public DOMPointReadOnly {
+class WEB_API DOMPoint final : public DOMPointReadOnly {
     WEB_PLATFORM_OBJECT(DOMPoint, DOMPointReadOnly);
     GC_DECLARE_ALLOCATOR(DOMPoint);
 
diff --git a/Libraries/LibWeb/HTML/AnimationFrameCallbackDriver.h b/Libraries/LibWeb/HTML/AnimationFrameCallbackDriver.h
index 65109b19a63..d6d623f3e7c 100644
--- a/Libraries/LibWeb/HTML/AnimationFrameCallbackDriver.h
+++ b/Libraries/LibWeb/HTML/AnimationFrameCallbackDriver.h
@@ -12,11 +12,12 @@
 #include <LibGC/Function.h>
 #include <LibGC/Ptr.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/Types.h>
 
 namespace Web::HTML {
 
-class AnimationFrameCallbackDriver final : public JS::Cell {
+class WEB_API AnimationFrameCallbackDriver final : public JS::Cell {
     GC_CELL(AnimationFrameCallbackDriver, JS::Cell);
     GC_DECLARE_ALLOCATOR(AnimationFrameCallbackDriver);
 
diff --git a/Libraries/LibWeb/HTML/AttributeNames.h b/Libraries/LibWeb/HTML/AttributeNames.h
index 757d13b8a35..446c9ade1e7 100644
--- a/Libraries/LibWeb/HTML/AttributeNames.h
+++ b/Libraries/LibWeb/HTML/AttributeNames.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/FlyString.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 namespace AttributeNames {
@@ -314,12 +315,12 @@ namespace AttributeNames {
     __ENUMERATE_HTML_ATTRIBUTE(willvalidate, "willvalidate")                             \
     __ENUMERATE_HTML_ATTRIBUTE(wrap, "wrap")
 
-#define __ENUMERATE_HTML_ATTRIBUTE(name, attribute) extern FlyString name;
+#define __ENUMERATE_HTML_ATTRIBUTE(name, attribute) extern WEB_API FlyString name;
 ENUMERATE_HTML_ATTRIBUTES
 #undef __ENUMERATE_HTML_ATTRIBUTE
 
 }
 
-bool is_boolean_attribute(FlyString const& attribute);
+WEB_API bool is_boolean_attribute(FlyString const& attribute);
 
 }
diff --git a/Libraries/LibWeb/HTML/AutocompleteElement.h b/Libraries/LibWeb/HTML/AutocompleteElement.h
index aa09318fa08..548aa5b5c5b 100644
--- a/Libraries/LibWeb/HTML/AutocompleteElement.h
+++ b/Libraries/LibWeb/HTML/AutocompleteElement.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/FormAssociatedElement.h>
 
 namespace Web::HTML {
@@ -19,7 +20,7 @@ private:                                                                 \
         return *this;                                                    \
     }
 
-class AutocompleteElement {
+class WEB_API AutocompleteElement {
 public:
     enum class AutofillMantle {
         Anchor,
diff --git a/Libraries/LibWeb/HTML/BrowsingContext.h b/Libraries/LibWeb/HTML/BrowsingContext.h
index 466de1f3aa3..0e5b09f8902 100644
--- a/Libraries/LibWeb/HTML/BrowsingContext.h
+++ b/Libraries/LibWeb/HTML/BrowsingContext.h
@@ -9,6 +9,7 @@
 #include <AK/Noncopyable.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibURL/Origin.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/NavigableContainer.h>
 #include <LibWeb/HTML/SandboxingFlagSet.h>
 #include <LibWeb/HTML/SessionHistoryEntry.h>
@@ -16,7 +17,7 @@
 
 namespace Web::HTML {
 
-class BrowsingContext final : public JS::Cell {
+class WEB_API BrowsingContext final : public JS::Cell {
     GC_CELL(BrowsingContext, JS::Cell);
     GC_DECLARE_ALLOCATOR(BrowsingContext);
 
@@ -127,7 +128,7 @@ URL::Origin determine_the_origin(Optional<URL::URL const&>, SandboxingFlagSet, O
 SandboxingFlagSet determine_the_creation_sandboxing_flags(BrowsingContext const&, GC::Ptr<DOM::Element> embedder);
 
 // FIXME: Find a better home for these
-bool url_matches_about_blank(URL::URL const& url);
+WEB_API bool url_matches_about_blank(URL::URL const& url);
 bool url_matches_about_srcdoc(URL::URL const& url);
 
 }
diff --git a/Libraries/LibWeb/HTML/CustomElements/CustomElementRegistry.h b/Libraries/LibWeb/HTML/CustomElements/CustomElementRegistry.h
index c9ab78b35ca..b2afa7fb7f2 100644
--- a/Libraries/LibWeb/HTML/CustomElements/CustomElementRegistry.h
+++ b/Libraries/LibWeb/HTML/CustomElements/CustomElementRegistry.h
@@ -8,6 +8,7 @@
 
 #include <AK/RefCounted.h>
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/CustomElements/CustomElementDefinition.h>
 
 namespace Web::HTML {
@@ -17,7 +18,7 @@ struct ElementDefinitionOptions {
 };
 
 // https://html.spec.whatwg.org/multipage/custom-elements.html#customelementregistry
-class CustomElementRegistry : public Bindings::PlatformObject {
+class WEB_API CustomElementRegistry : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(CustomElementRegistry, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(CustomElementRegistry);
 
diff --git a/Libraries/LibWeb/HTML/Dates.h b/Libraries/LibWeb/HTML/Dates.h
index 1fd6354e1ee..633342d1102 100644
--- a/Libraries/LibWeb/HTML/Dates.h
+++ b/Libraries/LibWeb/HTML/Dates.h
@@ -9,11 +9,12 @@
 #include <AK/Forward.h>
 #include <AK/Utf16String.h>
 #include <LibJS/Runtime/Date.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::HTML {
 
-u32 week_number_of_the_last_day(u64 year);
+WEB_API u32 week_number_of_the_last_day(u64 year);
 bool is_valid_week_string(Utf16View const& value);
 bool is_valid_month_string(Utf16View const& value);
 bool is_valid_date_string(Utf16View const& value);
diff --git a/Libraries/LibWeb/HTML/DedicatedWorkerGlobalScope.h b/Libraries/LibWeb/HTML/DedicatedWorkerGlobalScope.h
index 03d7d9c94b2..cc16113984b 100644
--- a/Libraries/LibWeb/HTML/DedicatedWorkerGlobalScope.h
+++ b/Libraries/LibWeb/HTML/DedicatedWorkerGlobalScope.h
@@ -8,11 +8,12 @@
 
 #include <LibWeb/Bindings/DedicatedWorkerGlobalScopeGlobalMixin.h>
 #include <LibWeb/Bindings/WorkerGlobalScopePrototype.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/WorkerGlobalScope.h>
 
 namespace Web::HTML {
 
-class DedicatedWorkerGlobalScope
+class WEB_API DedicatedWorkerGlobalScope
     : public WorkerGlobalScope
     , public Bindings::DedicatedWorkerGlobalScopeGlobalMixin {
     WEB_PLATFORM_OBJECT(DedicatedWorkerGlobalScope, WorkerGlobalScope);
diff --git a/Libraries/LibWeb/HTML/EventLoop/EventLoop.h b/Libraries/LibWeb/HTML/EventLoop/EventLoop.h
index edc16bfacea..14df272e813 100644
--- a/Libraries/LibWeb/HTML/EventLoop/EventLoop.h
+++ b/Libraries/LibWeb/HTML/EventLoop/EventLoop.h
@@ -12,12 +12,13 @@
 #include <LibCore/Forward.h>
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/EventLoop/TaskQueue.h>
 #include <LibWeb/HighResolutionTime/DOMHighResTimeStamp.h>
 
 namespace Web::HTML {
 
-class EventLoop : public JS::Cell {
+class WEB_API EventLoop : public JS::Cell {
     GC_CELL(EventLoop, JS::Cell);
     GC_DECLARE_ALLOCATOR(EventLoop);
 
@@ -140,10 +141,10 @@ private:
     GC::Ptr<GC::Function<void()>> m_rendering_task_function;
 };
 
-EventLoop& main_thread_event_loop();
-TaskID queue_a_task(HTML::Task::Source, GC::Ptr<EventLoop>, GC::Ptr<DOM::Document>, GC::Ref<GC::Function<void()>> steps);
-TaskID queue_global_task(HTML::Task::Source, JS::Object&, GC::Ref<GC::Function<void()>> steps);
-void queue_a_microtask(DOM::Document const*, GC::Ref<GC::Function<void()>> steps);
+WEB_API EventLoop& main_thread_event_loop();
+WEB_API TaskID queue_a_task(HTML::Task::Source, GC::Ptr<EventLoop>, GC::Ptr<DOM::Document>, GC::Ref<GC::Function<void()>> steps);
+WEB_API TaskID queue_global_task(HTML::Task::Source, JS::Object&, GC::Ref<GC::Function<void()>> steps);
+WEB_API void queue_a_microtask(DOM::Document const*, GC::Ref<GC::Function<void()>> steps);
 void perform_a_microtask_checkpoint();
 
 }
diff --git a/Libraries/LibWeb/HTML/EventLoop/Task.h b/Libraries/LibWeb/HTML/EventLoop/Task.h
index 83b00d7ea17..7e5032294bc 100644
--- a/Libraries/LibWeb/HTML/EventLoop/Task.h
+++ b/Libraries/LibWeb/HTML/EventLoop/Task.h
@@ -9,6 +9,7 @@
 #include <AK/DistinctNumeric.h>
 #include <LibGC/CellAllocator.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
@@ -109,14 +110,14 @@ private:
     GC::Ptr<DOM::Document const> m_document;
 };
 
-struct UniqueTaskSource {
+struct WEB_API UniqueTaskSource {
     UniqueTaskSource();
     ~UniqueTaskSource();
 
     Task::Source const source;
 };
 
-class ParallelQueue : public RefCounted<ParallelQueue> {
+class WEB_API ParallelQueue : public RefCounted<ParallelQueue> {
 public:
     static NonnullRefPtr<ParallelQueue> create();
     TaskID enqueue(GC::Ref<GC::Function<void()>>);
diff --git a/Libraries/LibWeb/HTML/EventNames.h b/Libraries/LibWeb/HTML/EventNames.h
index b03d852dbd4..42cc33483ac 100644
--- a/Libraries/LibWeb/HTML/EventNames.h
+++ b/Libraries/LibWeb/HTML/EventNames.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/FlyString.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML::EventNames {
 
@@ -134,7 +135,7 @@ namespace Web::HTML::EventNames {
     __ENUMERATE_HTML_EVENT(webkitAnimationStart)     \
     __ENUMERATE_HTML_EVENT(webkitTransitionEnd)
 
-#define __ENUMERATE_HTML_EVENT(name) extern FlyString name;
+#define __ENUMERATE_HTML_EVENT(name) extern WEB_API FlyString name;
 ENUMERATE_HTML_EVENTS
 #undef __ENUMERATE_HTML_EVENT
 
diff --git a/Libraries/LibWeb/HTML/FileFilter.h b/Libraries/LibWeb/HTML/FileFilter.h
index 8576bc18444..e33d5d5ebc7 100644
--- a/Libraries/LibWeb/HTML/FileFilter.h
+++ b/Libraries/LibWeb/HTML/FileFilter.h
@@ -10,6 +10,7 @@
 #include <AK/Variant.h>
 #include <AK/Vector.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
@@ -54,9 +55,9 @@ template<>
 ErrorOr<Web::HTML::FileFilter::Extension> decode(Decoder&);
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::FileFilter const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::FileFilter const&);
 
 template<>
-ErrorOr<Web::HTML::FileFilter> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::FileFilter> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/HTML/Focus.h b/Libraries/LibWeb/HTML/Focus.h
index 5d690e39028..53e85396fc2 100644
--- a/Libraries/LibWeb/HTML/Focus.h
+++ b/Libraries/LibWeb/HTML/Focus.h
@@ -8,6 +8,7 @@
 
 #include <AK/ByteString.h>
 #include <AK/Optional.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
@@ -19,7 +20,7 @@ enum class FocusTrigger : u8 {
     Other,
 };
 
-void run_focusing_steps(DOM::Node* new_focus_target, DOM::Node* fallback_target = nullptr, FocusTrigger focus_trigger = FocusTrigger::Other);
-void run_unfocusing_steps(DOM::Node* old_focus_target);
+WEB_API void run_focusing_steps(DOM::Node* new_focus_target, DOM::Node* fallback_target = nullptr, FocusTrigger focus_trigger = FocusTrigger::Other);
+WEB_API void run_unfocusing_steps(DOM::Node* old_focus_target);
 
 }
diff --git a/Libraries/LibWeb/HTML/FormAssociatedElement.h b/Libraries/LibWeb/HTML/FormAssociatedElement.h
index c93df33650e..21ee1d73f20 100644
--- a/Libraries/LibWeb/HTML/FormAssociatedElement.h
+++ b/Libraries/LibWeb/HTML/FormAssociatedElement.h
@@ -11,6 +11,7 @@
 #include <AK/WeakPtr.h>
 #include <LibWeb/Bindings/HTMLFormElementPrototype.h>
 #include <LibWeb/DOM/InputEventsTarget.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebIDL/Types.h>
 
@@ -66,7 +67,7 @@ enum class SelectionDirection {
     None,
 };
 
-class FormAssociatedElement {
+class WEB_API FormAssociatedElement {
 public:
     HTMLFormElement* form() { return m_form; }
     HTMLFormElement const* form() const { return m_form; }
@@ -179,7 +180,7 @@ enum class SelectionSource {
     DOM,
 };
 
-class FormAssociatedTextControlElement
+class WEB_API FormAssociatedTextControlElement
     : public FormAssociatedElement
     , public InputEventsTarget {
 public:
diff --git a/Libraries/LibWeb/HTML/GlobalEventHandlers.h b/Libraries/LibWeb/HTML/GlobalEventHandlers.h
index 4962eeb019f..64a3cc4332c 100644
--- a/Libraries/LibWeb/HTML/GlobalEventHandlers.h
+++ b/Libraries/LibWeb/HTML/GlobalEventHandlers.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 #define ENUMERATE_GLOBAL_EVENT_HANDLERS(E)                                    \
@@ -103,7 +104,7 @@
 
 namespace Web::HTML {
 
-class GlobalEventHandlers {
+class WEB_API GlobalEventHandlers {
 public:
     virtual ~GlobalEventHandlers();
 
diff --git a/Libraries/LibWeb/HTML/HTMLDataListElement.h b/Libraries/LibWeb/HTML/HTMLDataListElement.h
index 1d955ddb6d6..312d275eb8f 100644
--- a/Libraries/LibWeb/HTML/HTMLDataListElement.h
+++ b/Libraries/LibWeb/HTML/HTMLDataListElement.h
@@ -8,11 +8,12 @@
 
 #include <LibWeb/ARIA/Roles.h>
 #include <LibWeb/DOM/HTMLCollection.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLElement.h>
 
 namespace Web::HTML {
 
-class HTMLDataListElement final : public HTMLElement {
+class WEB_API HTMLDataListElement final : public HTMLElement {
     WEB_PLATFORM_OBJECT(HTMLDataListElement, HTMLElement);
     GC_DECLARE_ALLOCATOR(HTMLDataListElement);
 
diff --git a/Libraries/LibWeb/HTML/HTMLElement.h b/Libraries/LibWeb/HTML/HTMLElement.h
index 162c3c09ee2..33f97f32db8 100644
--- a/Libraries/LibWeb/HTML/HTMLElement.h
+++ b/Libraries/LibWeb/HTML/HTMLElement.h
@@ -8,6 +8,7 @@
 
 #include <AK/Optional.h>
 #include <LibWeb/DOM/Element.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/EventNames.h>
 #include <LibWeb/HTML/GlobalEventHandlers.h>
 #include <LibWeb/HTML/HTMLOrSVGElement.h>
@@ -70,7 +71,7 @@ enum class IsPopover {
     No,
 };
 
-class HTMLElement
+class WEB_API HTMLElement
     : public DOM::Element
     , public HTML::GlobalEventHandlers
     , public HTML::HTMLOrSVGElement<HTMLElement> {
diff --git a/Libraries/LibWeb/HTML/HTMLFrameElement.h b/Libraries/LibWeb/HTML/HTMLFrameElement.h
index e4328795608..f5a3cc515f2 100644
--- a/Libraries/LibWeb/HTML/HTMLFrameElement.h
+++ b/Libraries/LibWeb/HTML/HTMLFrameElement.h
@@ -6,12 +6,13 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/NavigableContainer.h>
 
 namespace Web::HTML {
 
 // NOTE: This element is marked as obsolete, but is still listed as required by the specification.
-class HTMLFrameElement final : public NavigableContainer {
+class WEB_API HTMLFrameElement final : public NavigableContainer {
     WEB_PLATFORM_OBJECT(HTMLFrameElement, NavigableContainer);
     GC_DECLARE_ALLOCATOR(HTMLFrameElement);
 
diff --git a/Libraries/LibWeb/HTML/HTMLHtmlElement.h b/Libraries/LibWeb/HTML/HTMLHtmlElement.h
index b715799ecf2..e77344e6052 100644
--- a/Libraries/LibWeb/HTML/HTMLHtmlElement.h
+++ b/Libraries/LibWeb/HTML/HTMLHtmlElement.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <LibWeb/ARIA/Roles.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLElement.h>
 
 namespace Web::HTML {
 
-class HTMLHtmlElement final : public HTMLElement {
+class WEB_API HTMLHtmlElement final : public HTMLElement {
     WEB_PLATFORM_OBJECT(HTMLHtmlElement, HTMLElement);
     GC_DECLARE_ALLOCATOR(HTMLHtmlElement);
 
diff --git a/Libraries/LibWeb/HTML/HTMLInputElement.h b/Libraries/LibWeb/HTML/HTMLInputElement.h
index 69dde7a2b01..bad18338a0d 100644
--- a/Libraries/LibWeb/HTML/HTMLInputElement.h
+++ b/Libraries/LibWeb/HTML/HTMLInputElement.h
@@ -12,6 +12,7 @@
 #include <LibRegex/Regex.h>
 #include <LibWeb/DOM/DocumentLoadEventDelayer.h>
 #include <LibWeb/DOM/Text.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/FileAPI/FileList.h>
 #include <LibWeb/HTML/AutocompleteElement.h>
 #include <LibWeb/HTML/ColorPickerUpdateState.h>
@@ -50,7 +51,7 @@ namespace Web::HTML {
     __ENUMERATE_HTML_INPUT_TYPE_ATTRIBUTE("reset", ResetButton)               \
     __ENUMERATE_HTML_INPUT_TYPE_ATTRIBUTE("button", Button)
 
-class HTMLInputElement final
+class WEB_API HTMLInputElement final
     : public HTMLElement
     , public FormAssociatedTextControlElement
     , public Layout::ImageProvider
diff --git a/Libraries/LibWeb/HTML/HTMLLinkElement.h b/Libraries/LibWeb/HTML/HTMLLinkElement.h
index 8c12a30d3ab..7d4813d950a 100644
--- a/Libraries/LibWeb/HTML/HTMLLinkElement.h
+++ b/Libraries/LibWeb/HTML/HTMLLinkElement.h
@@ -10,6 +10,7 @@
 #pragma once
 
 #include <LibWeb/DOM/DocumentLoadEventDelayer.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/FetchAlgorithms.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Requests.h>
 #include <LibWeb/HTML/CORSSettingAttribute.h>
@@ -18,7 +19,7 @@
 
 namespace Web::HTML {
 
-class HTMLLinkElement final
+class WEB_API HTMLLinkElement final
     : public HTMLElement
     , public ResourceClient {
     WEB_PLATFORM_OBJECT(HTMLLinkElement, HTMLElement);
diff --git a/Libraries/LibWeb/HTML/HTMLOptGroupElement.h b/Libraries/LibWeb/HTML/HTMLOptGroupElement.h
index 57f3cbdc577..dfa4a0e9187 100644
--- a/Libraries/LibWeb/HTML/HTMLOptGroupElement.h
+++ b/Libraries/LibWeb/HTML/HTMLOptGroupElement.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <LibWeb/ARIA/Roles.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLElement.h>
 
 namespace Web::HTML {
 
-class HTMLOptGroupElement final : public HTMLElement {
+class WEB_API HTMLOptGroupElement final : public HTMLElement {
     WEB_PLATFORM_OBJECT(HTMLOptGroupElement, HTMLElement);
     GC_DECLARE_ALLOCATOR(HTMLOptGroupElement);
 
diff --git a/Libraries/LibWeb/HTML/HTMLOptionElement.h b/Libraries/LibWeb/HTML/HTMLOptionElement.h
index f793c44e76e..bf6b2e10597 100644
--- a/Libraries/LibWeb/HTML/HTMLOptionElement.h
+++ b/Libraries/LibWeb/HTML/HTMLOptionElement.h
@@ -7,11 +7,12 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLElement.h>
 
 namespace Web::HTML {
 
-class HTMLOptionElement final : public HTMLElement {
+class WEB_API HTMLOptionElement final : public HTMLElement {
     WEB_PLATFORM_OBJECT(HTMLOptionElement, HTMLElement);
     GC_DECLARE_ALLOCATOR(HTMLOptionElement);
 
diff --git a/Libraries/LibWeb/HTML/HTMLSelectElement.h b/Libraries/LibWeb/HTML/HTMLSelectElement.h
index a1a55dce134..c3e0035e3a1 100644
--- a/Libraries/LibWeb/HTML/HTMLSelectElement.h
+++ b/Libraries/LibWeb/HTML/HTMLSelectElement.h
@@ -9,6 +9,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/AutocompleteElement.h>
 #include <LibWeb/HTML/FormAssociatedElement.h>
 #include <LibWeb/HTML/HTMLElement.h>
@@ -18,7 +19,7 @@
 
 namespace Web::HTML {
 
-class HTMLSelectElement final
+class WEB_API HTMLSelectElement final
     : public HTMLElement
     , public FormAssociatedElement
     , public AutocompleteElement {
diff --git a/Libraries/LibWeb/HTML/HTMLTextAreaElement.h b/Libraries/LibWeb/HTML/HTMLTextAreaElement.h
index 095d3ac4c87..cb4b02fd9fa 100644
--- a/Libraries/LibWeb/HTML/HTMLTextAreaElement.h
+++ b/Libraries/LibWeb/HTML/HTMLTextAreaElement.h
@@ -12,6 +12,7 @@
 #include <LibCore/Timer.h>
 #include <LibWeb/ARIA/Roles.h>
 #include <LibWeb/DOM/Text.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/AutocompleteElement.h>
 #include <LibWeb/HTML/FormAssociatedElement.h>
 #include <LibWeb/HTML/HTMLElement.h>
@@ -19,7 +20,7 @@
 
 namespace Web::HTML {
 
-class HTMLTextAreaElement final
+class WEB_API HTMLTextAreaElement final
     : public HTMLElement
     , public FormAssociatedTextControlElement
     , public AutocompleteElement {
diff --git a/Libraries/LibWeb/HTML/MessageEvent.h b/Libraries/LibWeb/HTML/MessageEvent.h
index 29cf7eb6acc..c61a72e524d 100644
--- a/Libraries/LibWeb/HTML/MessageEvent.h
+++ b/Libraries/LibWeb/HTML/MessageEvent.h
@@ -9,6 +9,7 @@
 
 #include <AK/FlyString.h>
 #include <LibWeb/DOM/Event.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
@@ -23,7 +24,7 @@ struct MessageEventInit : public DOM::EventInit {
     Vector<GC::Root<MessagePort>> ports;
 };
 
-class MessageEvent : public DOM::Event {
+class WEB_API MessageEvent : public DOM::Event {
     WEB_PLATFORM_OBJECT(MessageEvent, DOM::Event);
     GC_DECLARE_ALLOCATOR(MessageEvent);
 
diff --git a/Libraries/LibWeb/HTML/MessagePort.h b/Libraries/LibWeb/HTML/MessagePort.h
index d0946fb08d1..aad9e933172 100644
--- a/Libraries/LibWeb/HTML/MessagePort.h
+++ b/Libraries/LibWeb/HTML/MessagePort.h
@@ -15,12 +15,13 @@
 #include <LibIPC/Transport.h>
 #include <LibWeb/Bindings/Transferable.h>
 #include <LibWeb/DOM/EventTarget.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
 
 // https://html.spec.whatwg.org/multipage/web-messaging.html#message-ports
-class MessagePort final
+class WEB_API MessagePort final
     : public DOM::EventTarget
     , public Bindings::Transferable {
     WEB_PLATFORM_OBJECT(MessagePort, DOM::EventTarget);
diff --git a/Libraries/LibWeb/HTML/Navigable.h b/Libraries/LibWeb/HTML/Navigable.h
index 700a0d21887..827fc52daa0 100644
--- a/Libraries/LibWeb/HTML/Navigable.h
+++ b/Libraries/LibWeb/HTML/Navigable.h
@@ -12,6 +12,7 @@
 #include <LibJS/Heap/Cell.h>
 #include <LibWeb/Bindings/NavigationPrototype.h>
 #include <LibWeb/DOM/DocumentLoadEventDelayer.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/ActivateTab.h>
 #include <LibWeb/HTML/HistoryHandlingBehavior.h>
@@ -49,7 +50,7 @@ struct PaintConfig {
 };
 
 // https://html.spec.whatwg.org/multipage/document-sequences.html#navigable
-class Navigable : public JS::Cell
+class WEB_API Navigable : public JS::Cell
     , public Weakable<Navigable> {
     GC_CELL(Navigable, JS::Cell);
     GC_DECLARE_ALLOCATOR(Navigable);
@@ -292,7 +293,7 @@ private:
     RenderingThread m_rendering_thread;
 };
 
-HashTable<GC::RawRef<Navigable>>& all_navigables();
+WEB_API HashTable<GC::RawRef<Navigable>>& all_navigables();
 
 bool navigation_must_be_a_replace(URL::URL const& url, DOM::Document const& document);
 void finalize_a_cross_document_navigation(GC::Ref<Navigable>, HistoryHandlingBehavior, UserNavigationInvolvement, GC::Ref<SessionHistoryEntry>);
diff --git a/Libraries/LibWeb/HTML/NavigableContainer.h b/Libraries/LibWeb/HTML/NavigableContainer.h
index 95da4af5a2a..8ab47b64f0f 100644
--- a/Libraries/LibWeb/HTML/NavigableContainer.h
+++ b/Libraries/LibWeb/HTML/NavigableContainer.h
@@ -6,12 +6,13 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLElement.h>
 #include <LibWeb/HTML/Navigable.h>
 
 namespace Web::HTML {
 
-class NavigableContainer : public HTMLElement {
+class WEB_API NavigableContainer : public HTMLElement {
     WEB_PLATFORM_OBJECT(NavigableContainer, HTMLElement);
 
 public:
diff --git a/Libraries/LibWeb/HTML/NavigationObserver.h b/Libraries/LibWeb/HTML/NavigationObserver.h
index 2089d78847d..84144e9c1a6 100644
--- a/Libraries/LibWeb/HTML/NavigationObserver.h
+++ b/Libraries/LibWeb/HTML/NavigationObserver.h
@@ -9,11 +9,12 @@
 #include <LibGC/Function.h>
 #include <LibGC/Ptr.h>
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
 
-class NavigationObserver final : public Bindings::PlatformObject {
+class WEB_API NavigationObserver final : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(NavigationObserver, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(NavigationObserver);
 
diff --git a/Libraries/LibWeb/HTML/Numbers.h b/Libraries/LibWeb/HTML/Numbers.h
index 74b45e70c91..3961b02c18b 100644
--- a/Libraries/LibWeb/HTML/Numbers.h
+++ b/Libraries/LibWeb/HTML/Numbers.h
@@ -8,23 +8,24 @@
 
 #include <AK/Forward.h>
 #include <AK/String.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 #include <LibWeb/WebIDL/Types.h>
 
 namespace Web::HTML {
 
-Optional<i32> parse_integer(StringView string);
+WEB_API Optional<i32> parse_integer(StringView string);
 Optional<StringView> parse_integer_digits(StringView string);
 
-Optional<u32> parse_non_negative_integer(StringView string);
+WEB_API Optional<u32> parse_non_negative_integer(StringView string);
 Optional<StringView> parse_non_negative_integer_digits(StringView string);
 
 Optional<double> parse_floating_point_number(StringView string);
 Optional<double> parse_floating_point_number(Utf16String const& string);
 
-bool is_valid_floating_point_number(StringView string);
+WEB_API bool is_valid_floating_point_number(StringView string);
 bool is_valid_floating_point_number(Utf16String const& string);
 
-WebIDL::ExceptionOr<String> convert_non_negative_integer_to_string(JS::Realm&, WebIDL::Long);
+WEB_API WebIDL::ExceptionOr<String> convert_non_negative_integer_to_string(JS::Realm&, WebIDL::Long);
 
 }
diff --git a/Libraries/LibWeb/HTML/Parser/HTMLParser.h b/Libraries/LibWeb/HTML/Parser/HTMLParser.h
index 8b9a23dfe33..b06421532d2 100644
--- a/Libraries/LibWeb/HTML/Parser/HTMLParser.h
+++ b/Libraries/LibWeb/HTML/Parser/HTMLParser.h
@@ -9,6 +9,7 @@
 #include <LibGfx/Color.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibWeb/DOM/Node.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/Parser/HTMLTokenizer.h>
 #include <LibWeb/HTML/Parser/ListOfActiveFormattingElements.h>
 #include <LibWeb/HTML/Parser/StackOfOpenElements.h>
@@ -51,7 +52,7 @@ namespace Web::HTML {
     __ENUMERATE_INSERTION_MODE(AfterAfterBody)  \
     __ENUMERATE_INSERTION_MODE(AfterAfterFrameset)
 
-class HTMLParser final : public JS::Cell {
+class WEB_API HTMLParser final : public JS::Cell {
     GC_CELL(HTMLParser, JS::Cell);
     GC_DECLARE_ALLOCATOR(HTMLParser);
 
diff --git a/Libraries/LibWeb/HTML/Parser/HTMLToken.h b/Libraries/LibWeb/HTML/Parser/HTMLToken.h
index 2ac4b7394fd..050b3f13d07 100644
--- a/Libraries/LibWeb/HTML/Parser/HTMLToken.h
+++ b/Libraries/LibWeb/HTML/Parser/HTMLToken.h
@@ -13,12 +13,13 @@
 #include <AK/Types.h>
 #include <AK/Variant.h>
 #include <AK/Vector.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
 class HTMLTokenizer;
 
-class HTMLToken {
+class WEB_API HTMLToken {
     AK_MAKE_NONCOPYABLE(HTMLToken);
     AK_MAKE_DEFAULT_MOVABLE(HTMLToken);
 
diff --git a/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.h b/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.h
index 6684d1f18e5..87fd604bd0c 100644
--- a/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.h
+++ b/Libraries/LibWeb/HTML/Parser/HTMLTokenizer.h
@@ -12,6 +12,7 @@
 #include <AK/StringView.h>
 #include <AK/Types.h>
 #include <LibGC/Ptr.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/Parser/Entities.h>
 #include <LibWeb/HTML/Parser/HTMLToken.h>
@@ -100,7 +101,7 @@ namespace Web::HTML {
     __ENUMERATE_TOKENIZER_STATE(DecimalCharacterReference)                \
     __ENUMERATE_TOKENIZER_STATE(NumericCharacterReferenceEnd)
 
-class HTMLTokenizer {
+class WEB_API HTMLTokenizer {
 public:
     explicit HTMLTokenizer();
     explicit HTMLTokenizer(StringView input, ByteString const& encoding);
diff --git a/Libraries/LibWeb/HTML/PotentialCORSRequest.h b/Libraries/LibWeb/HTML/PotentialCORSRequest.h
index 14cd8f7e82f..a36d981d1ef 100644
--- a/Libraries/LibWeb/HTML/PotentialCORSRequest.h
+++ b/Libraries/LibWeb/HTML/PotentialCORSRequest.h
@@ -8,6 +8,7 @@
 
 #include <LibGC/Ptr.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Requests.h>
 #include <LibWeb/HTML/CORSSettingAttribute.h>
 
@@ -18,6 +19,6 @@ enum class SameOriginFallbackFlag {
     Yes,
 };
 
-[[nodiscard]] GC::Ref<Fetch::Infrastructure::Request> create_potential_CORS_request(JS::VM&, const URL::URL&, Optional<Fetch::Infrastructure::Request::Destination>, CORSSettingAttribute, SameOriginFallbackFlag = SameOriginFallbackFlag::No);
+[[nodiscard]] WEB_API GC::Ref<Fetch::Infrastructure::Request> create_potential_CORS_request(JS::VM&, const URL::URL&, Optional<Fetch::Infrastructure::Request::Destination>, CORSSettingAttribute, SameOriginFallbackFlag = SameOriginFallbackFlag::No);
 
 }
diff --git a/Libraries/LibWeb/HTML/Scripting/ClassicScript.h b/Libraries/LibWeb/HTML/Scripting/ClassicScript.h
index 88dcb1b7fa6..b86c1f93273 100644
--- a/Libraries/LibWeb/HTML/Scripting/ClassicScript.h
+++ b/Libraries/LibWeb/HTML/Scripting/ClassicScript.h
@@ -7,13 +7,14 @@
 #pragma once
 
 #include <LibJS/Script.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/Scripting/Script.h>
 
 namespace Web::HTML {
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#classic-script
-class ClassicScript final : public Script {
+class WEB_API ClassicScript final : public Script {
     GC_CELL(ClassicScript, Script);
     GC_DECLARE_ALLOCATOR(ClassicScript);
 
diff --git a/Libraries/LibWeb/HTML/Scripting/EnvironmentSettingsSnapshot.h b/Libraries/LibWeb/HTML/Scripting/EnvironmentSettingsSnapshot.h
index a3762905cf9..7c7a77050f8 100644
--- a/Libraries/LibWeb/HTML/Scripting/EnvironmentSettingsSnapshot.h
+++ b/Libraries/LibWeb/HTML/Scripting/EnvironmentSettingsSnapshot.h
@@ -6,13 +6,14 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/PolicyContainers.h>
 #include <LibWeb/HTML/Scripting/Environments.h>
 #include <LibWeb/HTML/Scripting/SerializedEnvironmentSettingsObject.h>
 
 namespace Web::HTML {
 
-class EnvironmentSettingsSnapshot final
+class WEB_API EnvironmentSettingsSnapshot final
     : public EnvironmentSettingsObject {
     GC_CELL(EnvironmentSettingsSnapshot, EnvironmentSettingsObject);
     GC_DECLARE_ALLOCATOR(EnvironmentSettingsSnapshot);
diff --git a/Libraries/LibWeb/HTML/Scripting/Environments.h b/Libraries/LibWeb/HTML/Scripting/Environments.h
index b2bfb12e70e..cc6dbe47d4e 100644
--- a/Libraries/LibWeb/HTML/Scripting/Environments.h
+++ b/Libraries/LibWeb/HTML/Scripting/Environments.h
@@ -11,6 +11,7 @@
 #include <LibJS/Forward.h>
 #include <LibURL/Origin.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/FetchRecord.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/EventLoop/EventLoop.h>
@@ -21,7 +22,7 @@
 namespace Web::HTML {
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#environment
-struct Environment : public JS::Cell {
+struct WEB_API Environment : public JS::Cell {
     GC_CELL(Environment, JS::Cell);
 
 public:
@@ -73,7 +74,7 @@ enum class RunScriptDecision {
 };
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object
-struct EnvironmentSettingsObject : public Environment {
+struct WEB_API EnvironmentSettingsObject : public Environment {
     GC_CELL(EnvironmentSettingsObject, Environment);
 
 public:
@@ -179,38 +180,38 @@ bool is_scripting_enabled(JS::Realm const&);
 bool is_scripting_disabled(JS::Realm const&);
 void prepare_to_run_script(JS::Realm&);
 void clean_up_after_running_script(JS::Realm const&);
-void prepare_to_run_callback(JS::Realm&);
-void clean_up_after_running_callback(JS::Realm const&);
-ModuleMap& module_map_of_realm(JS::Realm&);
-bool module_type_allowed(JS::Realm const&, StringView module_type);
+WEB_API void prepare_to_run_callback(JS::Realm&);
+WEB_API void clean_up_after_running_callback(JS::Realm const&);
+WEB_API ModuleMap& module_map_of_realm(JS::Realm&);
+WEB_API bool module_type_allowed(JS::Realm const&, StringView module_type);
 
-void add_module_to_resolved_module_set(JS::Realm&, String const& serialized_base_url, String const& normalized_specifier, Optional<URL::URL> const& as_url);
+WEB_API void add_module_to_resolved_module_set(JS::Realm&, String const& serialized_base_url, String const& normalized_specifier, Optional<URL::URL> const& as_url);
 
 EnvironmentSettingsObject& incumbent_settings_object();
-JS::Realm& incumbent_realm();
+WEB_API JS::Realm& incumbent_realm();
 JS::Object& incumbent_global_object();
 
 JS::Realm& current_principal_realm();
 EnvironmentSettingsObject& principal_realm_settings_object(JS::Realm&);
 EnvironmentSettingsObject& current_principal_settings_object();
 
-JS::Realm& principal_realm(GC::Ref<JS::Realm>);
-JS::Object& current_principal_global_object();
+WEB_API JS::Realm& principal_realm(GC::Ref<JS::Realm>);
+WEB_API JS::Object& current_principal_global_object();
 
-JS::Realm& relevant_realm(JS::Object const&);
+WEB_API JS::Realm& relevant_realm(JS::Object const&);
 JS::Realm& relevant_principal_realm(JS::Object const&);
 
-EnvironmentSettingsObject& relevant_settings_object(JS::Object const&);
+WEB_API EnvironmentSettingsObject& relevant_settings_object(JS::Object const&);
 EnvironmentSettingsObject& relevant_settings_object(DOM::Node const&);
-EnvironmentSettingsObject& relevant_principal_settings_object(JS::Object const&);
+WEB_API EnvironmentSettingsObject& relevant_principal_settings_object(JS::Object const&);
 
-JS::Object& relevant_global_object(JS::Object const&);
-JS::Object& relevant_principal_global_object(JS::Object const&);
+WEB_API JS::Object& relevant_global_object(JS::Object const&);
+WEB_API JS::Object& relevant_principal_global_object(JS::Object const&);
 
 JS::Realm& entry_realm();
 EnvironmentSettingsObject& entry_settings_object();
 JS::Object& entry_global_object();
-[[nodiscard]] bool is_secure_context(Environment const&);
+[[nodiscard]] WEB_API bool is_secure_context(Environment const&);
 [[nodiscard]] bool is_non_secure_context(Environment const&);
 
 }
diff --git a/Libraries/LibWeb/HTML/Scripting/ExceptionReporter.h b/Libraries/LibWeb/HTML/Scripting/ExceptionReporter.h
index 29e4597711e..eeaeb685389 100644
--- a/Libraries/LibWeb/HTML/Scripting/ExceptionReporter.h
+++ b/Libraries/LibWeb/HTML/Scripting/ExceptionReporter.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
@@ -16,7 +17,7 @@ enum class ErrorInPromise {
 };
 
 void report_exception_to_console(JS::Value, JS::Realm&, ErrorInPromise);
-void report_exception(JS::Completion const&, JS::Realm&);
+WEB_API void report_exception(JS::Completion const&, JS::Realm&);
 
 template<typename T>
 inline void report_exception(JS::ThrowCompletionOr<T> const& result, JS::Realm& realm)
diff --git a/Libraries/LibWeb/HTML/Scripting/Fetching.h b/Libraries/LibWeb/HTML/Scripting/Fetching.h
index ad2252e3a08..76c158f8680 100644
--- a/Libraries/LibWeb/HTML/Scripting/Fetching.h
+++ b/Libraries/LibWeb/HTML/Scripting/Fetching.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/FetchAlgorithms.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Requests.h>
 #include <LibWeb/HTML/CORSSettingAttribute.h>
@@ -24,8 +25,8 @@ enum class TopLevelModule {
 using OnFetchScriptComplete = GC::Ref<GC::Function<void(GC::Ptr<Script>)>>;
 using PerformTheFetchHook = GC::Ptr<GC::Function<WebIDL::ExceptionOr<void>(GC::Ref<Fetch::Infrastructure::Request>, TopLevelModule, Fetch::Infrastructure::FetchAlgorithms::ProcessResponseConsumeBodyFunction)>>;
 
-OnFetchScriptComplete create_on_fetch_script_complete(GC::Heap& heap, Function<void(GC::Ptr<Script>)> function);
-PerformTheFetchHook create_perform_the_fetch_hook(GC::Heap& heap, Function<WebIDL::ExceptionOr<void>(GC::Ref<Fetch::Infrastructure::Request>, TopLevelModule, Fetch::Infrastructure::FetchAlgorithms::ProcessResponseConsumeBodyFunction)> function);
+WEB_API OnFetchScriptComplete create_on_fetch_script_complete(GC::Heap& heap, Function<void(GC::Ptr<Script>)> function);
+WEB_API PerformTheFetchHook create_perform_the_fetch_hook(GC::Heap& heap, Function<WebIDL::ExceptionOr<void>(GC::Ref<Fetch::Infrastructure::Request>, TopLevelModule, Fetch::Infrastructure::FetchAlgorithms::ProcessResponseConsumeBodyFunction)> function);
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#script-fetch-options
 struct ScriptFetchOptions {
@@ -89,9 +90,9 @@ Optional<URL::URL> resolve_url_like_module_specifier(StringView specifier, URL::
 ScriptFetchOptions get_descendant_script_fetch_options(ScriptFetchOptions const& original_options, URL::URL const& url, EnvironmentSettingsObject& settings_object);
 String resolve_a_module_integrity_metadata(URL::URL const& url, EnvironmentSettingsObject& settings_object);
 WebIDL::ExceptionOr<void> fetch_classic_script(GC::Ref<HTMLScriptElement>, URL::URL const&, EnvironmentSettingsObject& settings_object, ScriptFetchOptions options, CORSSettingAttribute cors_setting, String character_encoding, OnFetchScriptComplete on_complete);
-WebIDL::ExceptionOr<void> fetch_classic_worker_script(URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, EnvironmentSettingsObject& settings_object, PerformTheFetchHook, OnFetchScriptComplete);
+WEB_API WebIDL::ExceptionOr<void> fetch_classic_worker_script(URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, EnvironmentSettingsObject& settings_object, PerformTheFetchHook, OnFetchScriptComplete);
 WebIDL::ExceptionOr<GC::Ref<ClassicScript>> fetch_a_classic_worker_imported_script(URL::URL const&, HTML::EnvironmentSettingsObject&, PerformTheFetchHook = nullptr);
-WebIDL::ExceptionOr<void> fetch_module_worker_script_graph(URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, EnvironmentSettingsObject& settings_object, PerformTheFetchHook, OnFetchScriptComplete);
+WEB_API WebIDL::ExceptionOr<void> fetch_module_worker_script_graph(URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, EnvironmentSettingsObject& settings_object, PerformTheFetchHook, OnFetchScriptComplete);
 WebIDL::ExceptionOr<void> fetch_worklet_module_worker_script_graph(URL::URL const&, EnvironmentSettingsObject& fetch_client, Fetch::Infrastructure::Request::Destination, EnvironmentSettingsObject& settings_object, PerformTheFetchHook, OnFetchScriptComplete);
 void fetch_external_module_script_graph(JS::Realm&, URL::URL const&, EnvironmentSettingsObject& settings_object, ScriptFetchOptions const&, OnFetchScriptComplete on_complete);
 void fetch_inline_module_script_graph(JS::Realm&, ByteString const& filename, ByteString const& source_text, URL::URL const& base_url, EnvironmentSettingsObject& settings_object, OnFetchScriptComplete on_complete);
diff --git a/Libraries/LibWeb/HTML/Scripting/ModuleMap.h b/Libraries/LibWeb/HTML/Scripting/ModuleMap.h
index c7f40435499..5889f742a34 100644
--- a/Libraries/LibWeb/HTML/Scripting/ModuleMap.h
+++ b/Libraries/LibWeb/HTML/Scripting/ModuleMap.h
@@ -9,6 +9,7 @@
 #include <LibGC/Function.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/Scripting/ModuleScript.h>
 
 namespace Web::HTML {
@@ -35,7 +36,7 @@ private:
 };
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#module-map
-class ModuleMap final : public JS::Cell {
+class WEB_API ModuleMap final : public JS::Cell {
     GC_CELL(ModuleMap, JS::Cell);
     GC_DECLARE_ALLOCATOR(ModuleMap);
 
diff --git a/Libraries/LibWeb/HTML/Scripting/ModuleScript.h b/Libraries/LibWeb/HTML/Scripting/ModuleScript.h
index 664b962790d..972ef4f51e9 100644
--- a/Libraries/LibWeb/HTML/Scripting/ModuleScript.h
+++ b/Libraries/LibWeb/HTML/Scripting/ModuleScript.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <LibJS/SourceTextModule.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/Scripting/Script.h>
 
 namespace Web::HTML {
@@ -25,7 +26,7 @@ private:
     virtual bool is_module_script() const final { return true; }
 };
 
-class JavaScriptModuleScript final : public ModuleScript {
+class WEB_API JavaScriptModuleScript final : public ModuleScript {
     GC_CELL(JavaScriptModuleScript, ModuleScript);
     GC_DECLARE_ALLOCATOR(JavaScriptModuleScript);
 
diff --git a/Libraries/LibWeb/HTML/Scripting/Script.h b/Libraries/LibWeb/HTML/Scripting/Script.h
index 4d33ec621dc..5a09bfdb30d 100644
--- a/Libraries/LibWeb/HTML/Scripting/Script.h
+++ b/Libraries/LibWeb/HTML/Scripting/Script.h
@@ -9,13 +9,14 @@
 #include <LibJS/Heap/Cell.h>
 #include <LibJS/Script.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#concept-script
 // https://whatpr.org/html/9893/webappapis.html#concept-script
-class Script
+class WEB_API Script
     : public JS::Cell
     , public JS::Script::HostDefined {
     GC_CELL(Script, JS::Cell);
diff --git a/Libraries/LibWeb/HTML/Scripting/SerializedEnvironmentSettingsObject.h b/Libraries/LibWeb/HTML/Scripting/SerializedEnvironmentSettingsObject.h
index 47a96cc7c17..66fa645cae8 100644
--- a/Libraries/LibWeb/HTML/Scripting/SerializedEnvironmentSettingsObject.h
+++ b/Libraries/LibWeb/HTML/Scripting/SerializedEnvironmentSettingsObject.h
@@ -10,6 +10,7 @@
 #include <LibIPC/Forward.h>
 #include <LibURL/Origin.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/SerializedPolicyContainer.h>
 
 namespace Web::HTML {
@@ -39,9 +40,9 @@ struct SerializedEnvironmentSettingsObject {
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::SerializedEnvironmentSettingsObject const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::SerializedEnvironmentSettingsObject const&);
 
 template<>
-ErrorOr<Web::HTML::SerializedEnvironmentSettingsObject> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::SerializedEnvironmentSettingsObject> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/HTML/Scripting/SimilarOriginWindowAgent.h b/Libraries/LibWeb/HTML/Scripting/SimilarOriginWindowAgent.h
index bccfa0ec114..0253b2938e5 100644
--- a/Libraries/LibWeb/HTML/Scripting/SimilarOriginWindowAgent.h
+++ b/Libraries/LibWeb/HTML/Scripting/SimilarOriginWindowAgent.h
@@ -12,6 +12,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Runtime/Agent.h>
 #include <LibWeb/DOM/MutationObserver.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/CustomElements/CustomElementReactionsStack.h>
 #include <LibWeb/HTML/Scripting/Agent.h>
@@ -50,6 +51,6 @@ private:
     }
 };
 
-SimilarOriginWindowAgent& relevant_similar_origin_window_agent(JS::Object const&);
+WEB_API SimilarOriginWindowAgent& relevant_similar_origin_window_agent(JS::Object const&);
 
 }
diff --git a/Libraries/LibWeb/HTML/Scripting/TemporaryExecutionContext.h b/Libraries/LibWeb/HTML/Scripting/TemporaryExecutionContext.h
index cdc01d15d12..3c42609ddbc 100644
--- a/Libraries/LibWeb/HTML/Scripting/TemporaryExecutionContext.h
+++ b/Libraries/LibWeb/HTML/Scripting/TemporaryExecutionContext.h
@@ -7,14 +7,14 @@
 #pragma once
 
 #include <LibGC/Ptr.h>
-#include <LibWeb/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
 // When JS is run from outside the context of any user script, we currently do not have a running execution context.
 // This results in a crash when we access VM::running_execution_context(). This is a spec issue. Until it is resolved,
 // this is a workaround to temporarily push an execution context.
-class [[nodiscard]] TemporaryExecutionContext {
+class [[nodiscard]] WEB_API TemporaryExecutionContext {
 public:
     enum class CallbacksEnabled {
         No,
diff --git a/Libraries/LibWeb/HTML/Scripting/WorkerEnvironmentSettingsObject.h b/Libraries/LibWeb/HTML/Scripting/WorkerEnvironmentSettingsObject.h
index 5b380eaa612..32e5a46f09c 100644
--- a/Libraries/LibWeb/HTML/Scripting/WorkerEnvironmentSettingsObject.h
+++ b/Libraries/LibWeb/HTML/Scripting/WorkerEnvironmentSettingsObject.h
@@ -8,11 +8,12 @@
 
 #include <LibURL/URL.h>
 #include <LibWeb/DOM/Document.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
 
-class WorkerEnvironmentSettingsObject final
+class WEB_API WorkerEnvironmentSettingsObject final
     : public EnvironmentSettingsObject {
     GC_CELL(WorkerEnvironmentSettingsObject, EnvironmentSettingsObject);
     GC_DECLARE_ALLOCATOR(WorkerEnvironmentSettingsObject);
diff --git a/Libraries/LibWeb/HTML/SelectItem.h b/Libraries/LibWeb/HTML/SelectItem.h
index 4ecf849839d..4be5e463939 100644
--- a/Libraries/LibWeb/HTML/SelectItem.h
+++ b/Libraries/LibWeb/HTML/SelectItem.h
@@ -8,6 +8,7 @@
 
 #include <AK/String.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLOptionElement.h>
 
 namespace Web::HTML {
@@ -35,21 +36,21 @@ using SelectItem = Variant<SelectItemOption, SelectItemOptionGroup, SelectItemSe
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::SelectItemOption const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::SelectItemOption const&);
 
 template<>
-ErrorOr<Web::HTML::SelectItemOption> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::SelectItemOption> decode(Decoder&);
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::SelectItemOptionGroup const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::SelectItemOptionGroup const&);
 
 template<>
-ErrorOr<Web::HTML::SelectItemOptionGroup> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::SelectItemOptionGroup> decode(Decoder&);
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::SelectItemSeparator const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::SelectItemSeparator const&);
 
 template<>
-ErrorOr<Web::HTML::SelectItemSeparator> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::SelectItemSeparator> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/HTML/SelectedFile.h b/Libraries/LibWeb/HTML/SelectedFile.h
index 8d1739231d8..ede21b24bc0 100644
--- a/Libraries/LibWeb/HTML/SelectedFile.h
+++ b/Libraries/LibWeb/HTML/SelectedFile.h
@@ -11,6 +11,7 @@
 #include <AK/Variant.h>
 #include <LibIPC/File.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
@@ -19,7 +20,7 @@ enum class AllowMultipleFiles {
     Yes,
 };
 
-class SelectedFile {
+class WEB_API SelectedFile {
 public:
     static ErrorOr<SelectedFile> from_file_path(ByteString const& file_path);
 
@@ -40,9 +41,9 @@ private:
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::SelectedFile const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::SelectedFile const&);
 
 template<>
-ErrorOr<Web::HTML::SelectedFile> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::SelectedFile> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/HTML/SessionHistoryTraversalQueue.h b/Libraries/LibWeb/HTML/SessionHistoryTraversalQueue.h
index 0fb5eb5329f..a0386655401 100644
--- a/Libraries/LibWeb/HTML/SessionHistoryTraversalQueue.h
+++ b/Libraries/LibWeb/HTML/SessionHistoryTraversalQueue.h
@@ -13,6 +13,7 @@
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
@@ -41,7 +42,7 @@ private:
 };
 
 // https://html.spec.whatwg.org/multipage/document-sequences.html#tn-session-history-traversal-queue
-class SessionHistoryTraversalQueue : public JS::Cell {
+class WEB_API SessionHistoryTraversalQueue : public JS::Cell {
     GC_CELL(SessionHistoryTraversalQueue, JS::Cell);
     GC_DECLARE_ALLOCATOR(SessionHistoryTraversalQueue);
 
diff --git a/Libraries/LibWeb/HTML/SharedWorkerGlobalScope.h b/Libraries/LibWeb/HTML/SharedWorkerGlobalScope.h
index ba477fe6c80..c9743087e6e 100644
--- a/Libraries/LibWeb/HTML/SharedWorkerGlobalScope.h
+++ b/Libraries/LibWeb/HTML/SharedWorkerGlobalScope.h
@@ -9,6 +9,7 @@
 #include <AK/HashTable.h>
 #include <LibJS/Forward.h>
 #include <LibWeb/Bindings/SharedWorkerGlobalScopeGlobalMixin.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/WorkerGlobalScope.h>
 
 namespace Web::HTML {
@@ -16,7 +17,7 @@ namespace Web::HTML {
 #define ENUMERATE_SHARED_WORKER_GLOBAL_SCOPE_EVENT_HANDLERS(E) \
     E(onconnect, HTML::EventNames::connect)
 
-class SharedWorkerGlobalScope
+class WEB_API SharedWorkerGlobalScope
     : public WorkerGlobalScope
     , public Bindings::SharedWorkerGlobalScopeGlobalMixin {
     WEB_PLATFORM_OBJECT(SharedWorkerGlobalScope, WorkerGlobalScope);
diff --git a/Libraries/LibWeb/HTML/Storage.h b/Libraries/LibWeb/HTML/Storage.h
index 8d0eb5c4c09..9657c6b06b9 100644
--- a/Libraries/LibWeb/HTML/Storage.h
+++ b/Libraries/LibWeb/HTML/Storage.h
@@ -9,13 +9,14 @@
 #pragma once
 
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/StorageAPI/StorageBottle.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::HTML {
 
 // https://html.spec.whatwg.org/multipage/webstorage.html#storage-2
-class Storage : public Bindings::PlatformObject {
+class WEB_API Storage : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(Storage, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(Storage);
 
diff --git a/Libraries/LibWeb/HTML/StructuredSerialize.h b/Libraries/LibWeb/HTML/StructuredSerialize.h
index d2298a112c1..d3195225c03 100644
--- a/Libraries/LibWeb/HTML/StructuredSerialize.h
+++ b/Libraries/LibWeb/HTML/StructuredSerialize.h
@@ -14,13 +14,14 @@
 #include <LibIPC/Encoder.h>
 #include <LibIPC/Message.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/StructuredSerializeTypes.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::HTML {
 
-class TransferDataEncoder {
+class WEB_API TransferDataEncoder {
 public:
     explicit TransferDataEncoder();
     explicit TransferDataEncoder(IPC::MessageBuffer&&);
@@ -42,7 +43,7 @@ private:
     IPC::Encoder m_encoder;
 };
 
-class TransferDataDecoder {
+class WEB_API TransferDataDecoder {
 public:
     explicit TransferDataDecoder(SerializationRecord const&);
     explicit TransferDataDecoder(TransferDataEncoder&&);
@@ -82,19 +83,19 @@ WebIDL::ExceptionOr<SerializationRecord> structured_serialize_internal(JS::VM&,
 WebIDL::ExceptionOr<JS::Value> structured_deserialize(JS::VM&, SerializationRecord const&, JS::Realm&, Optional<DeserializationMemory> = {});
 WebIDL::ExceptionOr<JS::Value> structured_deserialize_internal(JS::VM&, TransferDataDecoder&, JS::Realm&, DeserializationMemory&);
 
-WebIDL::ExceptionOr<SerializedTransferRecord> structured_serialize_with_transfer(JS::VM&, JS::Value, Vector<GC::Root<JS::Object>> const& transfer_list);
+WEB_API WebIDL::ExceptionOr<SerializedTransferRecord> structured_serialize_with_transfer(JS::VM&, JS::Value, Vector<GC::Root<JS::Object>> const& transfer_list);
 WebIDL::ExceptionOr<DeserializedTransferRecord> structured_deserialize_with_transfer(SerializedTransferRecord&, JS::Realm&);
-WebIDL::ExceptionOr<JS::Value> structured_deserialize_with_transfer_internal(TransferDataDecoder&, JS::Realm&);
+WEB_API WebIDL::ExceptionOr<JS::Value> structured_deserialize_with_transfer_internal(TransferDataDecoder&, JS::Realm&);
 
 }
 
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::TransferDataEncoder const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::TransferDataEncoder const&);
 
 template<>
-ErrorOr<Web::HTML::TransferDataEncoder> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::TransferDataEncoder> decode(Decoder&);
 
 template<>
 ErrorOr<void> encode(Encoder&, Web::HTML::SerializedTransferRecord const&);
diff --git a/Libraries/LibWeb/HTML/SyntaxHighlighter/SyntaxHighlighter.h b/Libraries/LibWeb/HTML/SyntaxHighlighter/SyntaxHighlighter.h
index 82a497f945b..95fb7082dcd 100644
--- a/Libraries/LibWeb/HTML/SyntaxHighlighter/SyntaxHighlighter.h
+++ b/Libraries/LibWeb/HTML/SyntaxHighlighter/SyntaxHighlighter.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <LibSyntax/Highlighter.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
@@ -20,7 +21,7 @@ enum class AugmentedTokenKind : u32 {
     __Count,
 };
 
-class SyntaxHighlighter : public Syntax::Highlighter {
+class WEB_API SyntaxHighlighter : public Syntax::Highlighter {
 public:
     SyntaxHighlighter() = default;
     virtual ~SyntaxHighlighter() override = default;
diff --git a/Libraries/LibWeb/HTML/TagNames.h b/Libraries/LibWeb/HTML/TagNames.h
index 56f882aaba4..aa299326f36 100644
--- a/Libraries/LibWeb/HTML/TagNames.h
+++ b/Libraries/LibWeb/HTML/TagNames.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/FlyString.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML::TagNames {
 
@@ -157,7 +158,7 @@ namespace Web::HTML::TagNames {
     __ENUMERATE_HTML_TAG(wbr, "wbr")               \
     __ENUMERATE_HTML_TAG(xmp, "xmp")
 
-#define __ENUMERATE_HTML_TAG(name, tag) extern FlyString name;
+#define __ENUMERATE_HTML_TAG(name, tag) extern WEB_API FlyString name;
 ENUMERATE_HTML_TAGS
 #undef __ENUMERATE_HTML_TAG
 
diff --git a/Libraries/LibWeb/HTML/TraversableNavigable.h b/Libraries/LibWeb/HTML/TraversableNavigable.h
index 03b246fbdc3..c36fbb8d563 100644
--- a/Libraries/LibWeb/HTML/TraversableNavigable.h
+++ b/Libraries/LibWeb/HTML/TraversableNavigable.h
@@ -9,6 +9,7 @@
 #pragma once
 
 #include <AK/Vector.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Geolocation/Geolocation.h>
 #include <LibWeb/HTML/Navigable.h>
 #include <LibWeb/HTML/NavigationType.h>
@@ -28,7 +29,7 @@
 namespace Web::HTML {
 
 // https://html.spec.whatwg.org/multipage/document-sequences.html#traversable-navigable
-class TraversableNavigable final : public Navigable {
+class WEB_API TraversableNavigable final : public Navigable {
     GC_CELL(TraversableNavigable, Navigable);
     GC_DECLARE_ALLOCATOR(TraversableNavigable);
 
diff --git a/Libraries/LibWeb/HTML/WebViewHints.h b/Libraries/LibWeb/HTML/WebViewHints.h
index d8daea24d36..a064e0aee2f 100644
--- a/Libraries/LibWeb/HTML/WebViewHints.h
+++ b/Libraries/LibWeb/HTML/WebViewHints.h
@@ -9,6 +9,7 @@
 #include <AK/Optional.h>
 #include <AK/Types.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/TokenizedFeatures.h>
 #include <LibWeb/PixelUnits.h>
@@ -30,9 +31,9 @@ struct WebViewHints {
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::HTML::WebViewHints const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::HTML::WebViewHints const&);
 
 template<>
-ErrorOr<Web::HTML::WebViewHints> decode(Decoder&);
+WEB_API ErrorOr<Web::HTML::WebViewHints> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/HTML/Window.h b/Libraries/LibWeb/HTML/Window.h
index 05e4709f352..3d7866d27ae 100644
--- a/Libraries/LibWeb/HTML/Window.h
+++ b/Libraries/LibWeb/HTML/Window.h
@@ -15,6 +15,7 @@
 #include <LibWeb/Bindings/Intrinsics.h>
 #include <LibWeb/Bindings/WindowGlobalMixin.h>
 #include <LibWeb/DOM/EventTarget.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/BarProp.h>
 #include <LibWeb/HTML/CrossOrigin/CrossOriginPropertyDescriptorMap.h>
@@ -64,7 +65,7 @@ struct SpecifierResolution {
     bool specifier_is_null_or_url_like_that_is_special { false };
 };
 
-class Window final
+class WEB_API Window final
     : public DOM::EventTarget
     , public GlobalEventHandlers
     , public WindowEventHandlers
diff --git a/Libraries/LibWeb/HTML/WindowOrWorkerGlobalScope.h b/Libraries/LibWeb/HTML/WindowOrWorkerGlobalScope.h
index d4d0ff0ca42..874031136c4 100644
--- a/Libraries/LibWeb/HTML/WindowOrWorkerGlobalScope.h
+++ b/Libraries/LibWeb/HTML/WindowOrWorkerGlobalScope.h
@@ -13,6 +13,7 @@
 #include <AK/IDAllocator.h>
 #include <AK/Variant.h>
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Request.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/ImageBitmap.h>
@@ -27,7 +28,7 @@ namespace Web::HTML {
 using TimerHandler = Variant<GC::Ref<WebIDL::CallbackType>, String>;
 
 // https://html.spec.whatwg.org/multipage/webappapis.html#windoworworkerglobalscope
-class WindowOrWorkerGlobalScopeMixin {
+class WEB_API WindowOrWorkerGlobalScopeMixin {
 public:
     virtual ~WindowOrWorkerGlobalScopeMixin();
 
diff --git a/Libraries/LibWeb/HTML/WindowProxy.h b/Libraries/LibWeb/HTML/WindowProxy.h
index 7b313ab4862..3fece0c4415 100644
--- a/Libraries/LibWeb/HTML/WindowProxy.h
+++ b/Libraries/LibWeb/HTML/WindowProxy.h
@@ -10,11 +10,12 @@
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
 #include <LibJS/Runtime/Object.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::HTML {
 
-class WindowProxy final : public JS::Object {
+class WEB_API WindowProxy final : public JS::Object {
     JS_OBJECT(WindowProxy, JS::Object);
     GC_DECLARE_ALLOCATOR(WindowProxy);
 
diff --git a/Libraries/LibWeb/HTML/WorkerDebugConsoleClient.h b/Libraries/LibWeb/HTML/WorkerDebugConsoleClient.h
index fc11e00af67..ef95e1c9c33 100644
--- a/Libraries/LibWeb/HTML/WorkerDebugConsoleClient.h
+++ b/Libraries/LibWeb/HTML/WorkerDebugConsoleClient.h
@@ -9,12 +9,13 @@
 #include <AK/RefCounted.h>
 #include <AK/Weakable.h>
 #include <LibJS/Console.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
 // NOTE: Temporary class to handle console messages from inside Workers
 
-class WorkerDebugConsoleClient final : public JS::ConsoleClient {
+class WEB_API WorkerDebugConsoleClient final : public JS::ConsoleClient {
     GC_CELL(WorkerDebugConsoleClient, JS::ConsoleClient);
     GC_DECLARE_ALLOCATOR(WorkerDebugConsoleClient);
 
diff --git a/Libraries/LibWeb/HTML/WorkerGlobalScope.h b/Libraries/LibWeb/HTML/WorkerGlobalScope.h
index d5cab471c90..df5a3302454 100644
--- a/Libraries/LibWeb/HTML/WorkerGlobalScope.h
+++ b/Libraries/LibWeb/HTML/WorkerGlobalScope.h
@@ -12,6 +12,7 @@
 #include <LibCore/Socket.h>
 #include <LibURL/URL.h>
 #include <LibWeb/DOM/EventTarget.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/Scripting/Fetching.h>
 #include <LibWeb/HTML/UniversalGlobalScope.h>
@@ -33,7 +34,7 @@ namespace Web::HTML {
 // https://html.spec.whatwg.org/multipage/workers.html#the-workerglobalscope-common-interface
 // WorkerGlobalScope is the base class of each real WorkerGlobalScope that will be created when the
 // user agent runs the run a worker algorithm.
-class WorkerGlobalScope
+class WEB_API WorkerGlobalScope
     : public DOM::EventTarget
     , public WindowOrWorkerGlobalScopeMixin
     , public UniversalGlobalScopeMixin {
diff --git a/Libraries/LibWeb/HTML/WorkerLocation.h b/Libraries/LibWeb/HTML/WorkerLocation.h
index 8caace9089b..87556ef05d6 100644
--- a/Libraries/LibWeb/HTML/WorkerLocation.h
+++ b/Libraries/LibWeb/HTML/WorkerLocation.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 
 namespace Web::HTML {
 
 // https://html.spec.whatwg.org/multipage/workers.html#worker-locations
-class WorkerLocation : public Bindings::PlatformObject {
+class WEB_API WorkerLocation : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(WorkerLocation, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(WorkerLocation);
 
diff --git a/Libraries/LibWeb/HighResolutionTime/TimeOrigin.h b/Libraries/LibWeb/HighResolutionTime/TimeOrigin.h
index 9ee9c61fb13..43e5266da1c 100644
--- a/Libraries/LibWeb/HighResolutionTime/TimeOrigin.h
+++ b/Libraries/LibWeb/HighResolutionTime/TimeOrigin.h
@@ -8,6 +8,7 @@
 #pragma once
 
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HighResolutionTime/DOMHighResTimeStamp.h>
 
 namespace Web::HighResolutionTime {
@@ -18,8 +19,8 @@ DOMHighResTimeStamp coarsen_time(DOMHighResTimeStamp timestamp, bool cross_origi
 DOMHighResTimeStamp current_high_resolution_time(JS::Object const&);
 DOMHighResTimeStamp relative_high_resolution_time(DOMHighResTimeStamp, JS::Object const&);
 DOMHighResTimeStamp relative_high_resolution_coarsen_time(DOMHighResTimeStamp, JS::Object const&);
-DOMHighResTimeStamp coarsened_shared_current_time(bool cross_origin_isolated_capability = false);
+WEB_API DOMHighResTimeStamp coarsened_shared_current_time(bool cross_origin_isolated_capability = false);
 DOMHighResTimeStamp wall_clock_unsafe_current_time();
-DOMHighResTimeStamp unsafe_shared_current_time();
+WEB_API DOMHighResTimeStamp unsafe_shared_current_time();
 
 }
diff --git a/Libraries/LibWeb/Infra/JSON.h b/Libraries/LibWeb/Infra/JSON.h
index 6eeddafb930..690f4f05f85 100644
--- a/Libraries/LibWeb/Infra/JSON.h
+++ b/Libraries/LibWeb/Infra/JSON.h
@@ -8,6 +8,7 @@
 
 #include <AK/Forward.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Infra {
@@ -24,6 +25,6 @@ WebIDL::ExceptionOr<JS::Value> parse_json_bytes_to_javascript_value(JS::Realm&,
 WebIDL::ExceptionOr<String> serialize_javascript_value_to_json_string(JS::VM&, JS::Value);
 WebIDL::ExceptionOr<ByteBuffer> serialize_javascript_value_to_json_bytes(JS::VM&, JS::Value);
 String serialize_an_infra_value_to_a_json_string(JS::Realm&, JSONTopLevel const&);
-ByteBuffer serialize_an_infra_value_to_json_bytes(JS::Realm&, JSONTopLevel const&);
+WEB_API ByteBuffer serialize_an_infra_value_to_json_bytes(JS::Realm&, JSONTopLevel const&);
 
 }
diff --git a/Libraries/LibWeb/Infra/Strings.h b/Libraries/LibWeb/Infra/Strings.h
index f0caacdb95d..cadbc81f9a0 100644
--- a/Libraries/LibWeb/Infra/Strings.h
+++ b/Libraries/LibWeb/Infra/Strings.h
@@ -10,17 +10,18 @@
 #pragma once
 
 #include <AK/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Infra {
 
-String normalize_newlines(String const&);
-Utf16String normalize_newlines(Utf16String const&);
-ErrorOr<String> strip_and_collapse_whitespace(StringView string);
+WEB_API String normalize_newlines(String const&);
+WEB_API Utf16String normalize_newlines(Utf16String const&);
+WEB_API ErrorOr<String> strip_and_collapse_whitespace(StringView string);
 Utf16String strip_and_collapse_whitespace(Utf16String const& string);
-bool is_code_unit_prefix(StringView potential_prefix, StringView input);
-ErrorOr<String> convert_to_scalar_value_string(StringView string);
+WEB_API bool is_code_unit_prefix(StringView potential_prefix, StringView input);
+WEB_API ErrorOr<String> convert_to_scalar_value_string(StringView string);
 ByteBuffer isomorphic_encode(StringView input);
-String isomorphic_decode(ReadonlyBytes input);
+WEB_API String isomorphic_decode(ReadonlyBytes input);
 bool code_unit_less_than(StringView a, StringView b);
 
 }
diff --git a/Libraries/LibWeb/Internals/Internals.h b/Libraries/LibWeb/Internals/Internals.h
index 274e13cd5f7..194ed083a57 100644
--- a/Libraries/LibWeb/Internals/Internals.h
+++ b/Libraries/LibWeb/Internals/Internals.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Internals/InternalAnimationTimeline.h>
 #include <LibWeb/Internals/InternalsBase.h>
 #include <LibWeb/UIEvents/MouseButton.h>
@@ -13,7 +14,7 @@
 
 namespace Web::Internals {
 
-class Internals final : public InternalsBase {
+class WEB_API Internals final : public InternalsBase {
     WEB_PLATFORM_OBJECT(Internals, InternalsBase);
     GC_DECLARE_ALLOCATOR(Internals);
 
diff --git a/Libraries/LibWeb/Internals/InternalsBase.h b/Libraries/LibWeb/Internals/InternalsBase.h
index 192b9ed7b8e..d284e19687b 100644
--- a/Libraries/LibWeb/Internals/InternalsBase.h
+++ b/Libraries/LibWeb/Internals/InternalsBase.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Internals {
 
-class InternalsBase : public Bindings::PlatformObject {
+class WEB_API InternalsBase : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(InternalsBase, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(InternalsBase);
 
diff --git a/Libraries/LibWeb/Internals/WebUI.h b/Libraries/LibWeb/Internals/WebUI.h
index d1b067bc6f8..6292fe85072 100644
--- a/Libraries/LibWeb/Internals/WebUI.h
+++ b/Libraries/LibWeb/Internals/WebUI.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <LibJS/Runtime/Value.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Internals/InternalsBase.h>
 
 namespace Web::Internals {
 
-class WebUI final : public InternalsBase {
+class WEB_API WebUI final : public InternalsBase {
     WEB_PLATFORM_OBJECT(WebUI, InternalsBase);
     GC_DECLARE_ALLOCATOR(WebUI);
 
diff --git a/Libraries/LibWeb/Layout/Box.h b/Libraries/LibWeb/Layout/Box.h
index 854e14952f2..ef072864518 100644
--- a/Libraries/LibWeb/Layout/Box.h
+++ b/Libraries/LibWeb/Layout/Box.h
@@ -8,6 +8,7 @@
 
 #include <AK/OwnPtr.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Layout/Node.h>
 
 namespace Web::Layout {
@@ -24,7 +25,7 @@ struct IntrinsicSizes {
     HashMap<CSSPixels, Optional<CSSPixels>> max_content_height;
 };
 
-class Box : public NodeWithStyleAndBoxModelMetrics {
+class WEB_API Box : public NodeWithStyleAndBoxModelMetrics {
     GC_CELL(Box, NodeWithStyleAndBoxModelMetrics);
 
 public:
diff --git a/Libraries/LibWeb/Layout/Label.h b/Libraries/LibWeb/Layout/Label.h
index 5ba546938d0..f8d4628c0ee 100644
--- a/Libraries/LibWeb/Layout/Label.h
+++ b/Libraries/LibWeb/Layout/Label.h
@@ -6,12 +6,13 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLLabelElement.h>
 #include <LibWeb/Layout/BlockContainer.h>
 
 namespace Web::Layout {
 
-class Label final : public BlockContainer {
+class WEB_API Label final : public BlockContainer {
     GC_CELL(Label, BlockContainer);
     GC_DECLARE_ALLOCATOR(Label);
 
diff --git a/Libraries/LibWeb/Layout/Node.h b/Libraries/LibWeb/Layout/Node.h
index 92dfb60d73a..70b38754098 100644
--- a/Libraries/LibWeb/Layout/Node.h
+++ b/Libraries/LibWeb/Layout/Node.h
@@ -12,6 +12,7 @@
 #include <LibJS/Heap/Cell.h>
 #include <LibWeb/CSS/StyleValues/ImageStyleValue.h>
 #include <LibWeb/DOM/Document.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Painting/DisplayListRecordingContext.h>
 #include <LibWeb/Painting/Paintable.h>
@@ -30,7 +31,7 @@ enum class LayoutMode {
     IntrinsicSizing,
 };
 
-class Node
+class WEB_API Node
     : public JS::Cell
     , public TreeNode<Node> {
     GC_CELL(Node, JS::Cell);
@@ -231,7 +232,7 @@ private:
     u32 m_initial_quote_nesting_level { 0 };
 };
 
-class NodeWithStyle : public Node {
+class WEB_API NodeWithStyle : public Node {
     GC_CELL(NodeWithStyle, Node);
 
 public:
diff --git a/Libraries/LibWeb/Layout/SVGGraphicsBox.h b/Libraries/LibWeb/Layout/SVGGraphicsBox.h
index 05bf851d41e..9d19619f2f6 100644
--- a/Libraries/LibWeb/Layout/SVGGraphicsBox.h
+++ b/Libraries/LibWeb/Layout/SVGGraphicsBox.h
@@ -6,13 +6,14 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Layout/SVGBox.h>
 #include <LibWeb/SVG/SVGElement.h>
 #include <LibWeb/SVG/SVGGraphicsElement.h>
 
 namespace Web::Layout {
 
-class SVGGraphicsBox : public SVGBox {
+class WEB_API SVGGraphicsBox : public SVGBox {
     GC_CELL(SVGGraphicsBox, SVGBox);
 
 public:
diff --git a/Libraries/LibWeb/Loader/ContentFilter.h b/Libraries/LibWeb/Loader/ContentFilter.h
index 2786d835bf1..d1a00a95421 100644
--- a/Libraries/LibWeb/Loader/ContentFilter.h
+++ b/Libraries/LibWeb/Loader/ContentFilter.h
@@ -9,10 +9,11 @@
 #include <AK/String.h>
 #include <AK/Vector.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 
 namespace Web {
 
-class ContentFilter {
+class WEB_API ContentFilter {
 public:
     static ContentFilter& the();
 
diff --git a/Libraries/LibWeb/Loader/FileRequest.h b/Libraries/LibWeb/Loader/FileRequest.h
index 8e7828915e6..a186aa853d3 100644
--- a/Libraries/LibWeb/Loader/FileRequest.h
+++ b/Libraries/LibWeb/Loader/FileRequest.h
@@ -10,10 +10,11 @@
 #include <AK/Error.h>
 #include <AK/Function.h>
 #include <AK/Swift.h>
+#include <LibWeb/Export.h>
 
 namespace Web {
 
-class FileRequest {
+class WEB_API FileRequest {
 public:
     FileRequest(ByteString path, ESCAPING Function<void(ErrorOr<i32>)> on_file_request_finish);
 
diff --git a/Libraries/LibWeb/Loader/GeneratedPagesLoader.h b/Libraries/LibWeb/Loader/GeneratedPagesLoader.h
index db9d5994a66..aa1ee8040f3 100644
--- a/Libraries/LibWeb/Loader/GeneratedPagesLoader.h
+++ b/Libraries/LibWeb/Loader/GeneratedPagesLoader.h
@@ -6,13 +6,14 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Responses.h>
 #include <LibWeb/Loader/Resource.h>
 
 namespace Web {
 
-void set_browser_process_command_line(StringView command_line);
-void set_browser_process_executable_path(StringView executable_path);
+WEB_API void set_browser_process_command_line(StringView command_line);
+WEB_API void set_browser_process_executable_path(StringView executable_path);
 
 ErrorOr<String> load_error_page(URL::URL const&, StringView error_message);
 
diff --git a/Libraries/LibWeb/Loader/LoadRequest.h b/Libraries/LibWeb/Loader/LoadRequest.h
index 58c2125e33b..0f2bc69a447 100644
--- a/Libraries/LibWeb/Loader/LoadRequest.h
+++ b/Libraries/LibWeb/Loader/LoadRequest.h
@@ -11,12 +11,13 @@
 #include <AK/Time.h>
 #include <LibCore/ElapsedTimer.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Page/Page.h>
 
 namespace Web {
 
-class LoadRequest {
+class WEB_API LoadRequest {
 public:
     LoadRequest();
 
diff --git a/Libraries/LibWeb/Loader/ProxyMappings.h b/Libraries/LibWeb/Loader/ProxyMappings.h
index 4d03c405fee..0b9c95409bf 100644
--- a/Libraries/LibWeb/Loader/ProxyMappings.h
+++ b/Libraries/LibWeb/Loader/ProxyMappings.h
@@ -10,10 +10,11 @@
 #include <AK/Vector.h>
 #include <LibCore/Proxy.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 
 namespace Web {
 
-class ProxyMappings {
+class WEB_API ProxyMappings {
 public:
     static ProxyMappings& the();
 
diff --git a/Libraries/LibWeb/Loader/ResourceLoader.h b/Libraries/LibWeb/Loader/ResourceLoader.h
index 634280b578e..60d93603afa 100644
--- a/Libraries/LibWeb/Loader/ResourceLoader.h
+++ b/Libraries/LibWeb/Loader/ResourceLoader.h
@@ -13,12 +13,13 @@
 #include <LibCore/EventReceiver.h>
 #include <LibRequests/Forward.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Loader/Resource.h>
 #include <LibWeb/Loader/UserAgent.h>
 
 namespace Web {
 
-class ResourceLoader : public Core::EventReceiver {
+class WEB_API ResourceLoader : public Core::EventReceiver {
     C_OBJECT_ABSTRACT(ResourceLoader)
 public:
     static void initialize(GC::Heap&, NonnullRefPtr<Requests::RequestClient>);
diff --git a/Libraries/LibWeb/MimeSniff/MimeType.h b/Libraries/LibWeb/MimeSniff/MimeType.h
index dbe411854ad..fbeb9038dda 100644
--- a/Libraries/LibWeb/MimeSniff/MimeType.h
+++ b/Libraries/LibWeb/MimeSniff/MimeType.h
@@ -9,6 +9,7 @@
 
 #include <AK/HashMap.h>
 #include <AK/String.h>
+#include <LibWeb/Export.h>
 
 namespace Web::MimeSniff {
 
@@ -36,7 +37,7 @@ static constexpr Array s_javascript_mime_type_essence_strings = {
 };
 
 // https://mimesniff.spec.whatwg.org/#mime-type
-class MimeType {
+class WEB_API MimeType {
 public:
     [[nodiscard]] static MimeType create(String type, String subtype);
     [[nodiscard]] static Optional<MimeType> parse(StringView);
@@ -88,6 +89,6 @@ private:
     String m_cached_essence;
 };
 
-String minimise_a_supported_mime_type(MimeType const&);
+WEB_API String minimise_a_supported_mime_type(MimeType const&);
 
 }
diff --git a/Libraries/LibWeb/MimeSniff/Resource.h b/Libraries/LibWeb/MimeSniff/Resource.h
index 97ced2235ee..9b9c2bdfdc9 100644
--- a/Libraries/LibWeb/MimeSniff/Resource.h
+++ b/Libraries/LibWeb/MimeSniff/Resource.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/MimeSniff/MimeType.h>
 
 namespace Web::MimeSniff {
@@ -30,7 +31,7 @@ struct SniffingConfiguration {
 };
 
 // https://mimesniff.spec.whatwg.org/#resource
-class Resource {
+class WEB_API Resource {
 public:
     static Resource create(ReadonlyBytes data, SniffingConfiguration configuration = {});
     static MimeType sniff(ReadonlyBytes data, SniffingConfiguration configuration = {});
diff --git a/Libraries/LibWeb/MixedContent/AbstractOperations.h b/Libraries/LibWeb/MixedContent/AbstractOperations.h
index 8696dd97694..9bc027200c4 100644
--- a/Libraries/LibWeb/MixedContent/AbstractOperations.h
+++ b/Libraries/LibWeb/MixedContent/AbstractOperations.h
@@ -7,12 +7,13 @@
 #pragma once
 
 #include <LibGC/Ptr.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/RequestOrResponseBlocking.h>
 #include <LibWeb/HTML/Scripting/Environments.h>
 
 namespace Web::MixedContent {
 
-void upgrade_a_mixed_content_request_to_a_potentially_trustworthy_url_if_appropriate(Fetch::Infrastructure::Request&);
+WEB_API void upgrade_a_mixed_content_request_to_a_potentially_trustworthy_url_if_appropriate(Fetch::Infrastructure::Request&);
 
 enum class ProhibitsMixedSecurityContexts {
     ProhibitsMixedSecurityContexts,
@@ -21,8 +22,8 @@ enum class ProhibitsMixedSecurityContexts {
 
 ProhibitsMixedSecurityContexts does_settings_prohibit_mixed_security_contexts(GC::Ptr<HTML::EnvironmentSettingsObject>);
 
-Fetch::Infrastructure::RequestOrResponseBlocking should_fetching_request_be_blocked_as_mixed_content(Fetch::Infrastructure::Request&);
+WEB_API Fetch::Infrastructure::RequestOrResponseBlocking should_fetching_request_be_blocked_as_mixed_content(Fetch::Infrastructure::Request&);
 
-Fetch::Infrastructure::RequestOrResponseBlocking should_response_to_request_be_blocked_as_mixed_content(Fetch::Infrastructure::Request&, GC::Ref<Fetch::Infrastructure::Response>&);
+WEB_API Fetch::Infrastructure::RequestOrResponseBlocking should_response_to_request_be_blocked_as_mixed_content(Fetch::Infrastructure::Request&, GC::Ref<Fetch::Infrastructure::Response>&);
 
 }
diff --git a/Libraries/LibWeb/Namespace.h b/Libraries/LibWeb/Namespace.h
index 17eb9f6bb20..339e385ca40 100644
--- a/Libraries/LibWeb/Namespace.h
+++ b/Libraries/LibWeb/Namespace.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/FlyString.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Namespace {
 
@@ -18,7 +19,7 @@ namespace Web::Namespace {
     __ENUMERATE_NAMESPACE(XML, "http://www.w3.org/XML/1998/namespace")  \
     __ENUMERATE_NAMESPACE(XMLNS, "http://www.w3.org/2000/xmlns/")
 
-#define __ENUMERATE_NAMESPACE(name, namespace_) extern FlyString name;
+#define __ENUMERATE_NAMESPACE(name, namespace_) extern WEB_API FlyString name;
 ENUMERATE_NAMESPACES
 #undef __ENUMERATE_NAMESPACE
 
diff --git a/Libraries/LibWeb/Page/EventHandler.h b/Libraries/LibWeb/Page/EventHandler.h
index 037985609f0..7e9f94647d9 100644
--- a/Libraries/LibWeb/Page/EventHandler.h
+++ b/Libraries/LibWeb/Page/EventHandler.h
@@ -13,6 +13,7 @@
 #include <LibGfx/Forward.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibUnicode/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Page/EventResult.h>
 #include <LibWeb/Page/InputEvent.h>
@@ -21,7 +22,7 @@
 
 namespace Web {
 
-class EventHandler {
+class WEB_API EventHandler {
 public:
     explicit EventHandler(Badge<HTML::Navigable>, HTML::Navigable&);
     ~EventHandler();
diff --git a/Libraries/LibWeb/Page/InputEvent.h b/Libraries/LibWeb/Page/InputEvent.h
index 6e3f31902ec..afb4c12f6e8 100644
--- a/Libraries/LibWeb/Page/InputEvent.h
+++ b/Libraries/LibWeb/Page/InputEvent.h
@@ -11,6 +11,7 @@
 #include <AK/Vector.h>
 #include <LibGfx/Point.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/SelectedFile.h>
 #include <LibWeb/PixelUnits.h>
 #include <LibWeb/UIEvents/KeyCode.h>
@@ -22,7 +23,7 @@ struct BrowserInputData {
     virtual ~BrowserInputData() = default;
 };
 
-struct KeyEvent {
+struct WEB_API KeyEvent {
     enum class Type {
         KeyDown,
         KeyUp,
@@ -39,7 +40,7 @@ struct KeyEvent {
     OwnPtr<BrowserInputData> browser_data;
 };
 
-struct MouseEvent {
+struct WEB_API MouseEvent {
     enum class Type {
         MouseDown,
         MouseUp,
@@ -63,7 +64,7 @@ struct MouseEvent {
     OwnPtr<BrowserInputData> browser_data;
 };
 
-struct DragEvent {
+struct WEB_API DragEvent {
     enum class Type {
         DragStart,
         DragMove,
@@ -97,21 +98,21 @@ struct QueuedInputEvent {
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::KeyEvent const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::KeyEvent const&);
 
 template<>
-ErrorOr<Web::KeyEvent> decode(Decoder&);
+WEB_API ErrorOr<Web::KeyEvent> decode(Decoder&);
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::MouseEvent const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::MouseEvent const&);
 
 template<>
-ErrorOr<Web::MouseEvent> decode(Decoder&);
+WEB_API ErrorOr<Web::MouseEvent> decode(Decoder&);
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::DragEvent const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::DragEvent const&);
 
 template<>
-ErrorOr<Web::DragEvent> decode(Decoder&);
+WEB_API ErrorOr<Web::DragEvent> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/Page/Page.h b/Libraries/LibWeb/Page/Page.h
index 174c60825ed..5c4903a27a0 100644
--- a/Libraries/LibWeb/Page/Page.h
+++ b/Libraries/LibWeb/Page/Page.h
@@ -25,6 +25,7 @@
 #include <LibWeb/CSS/PreferredContrast.h>
 #include <LibWeb/CSS/PreferredMotion.h>
 #include <LibWeb/Cookie/Cookie.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/ActivateTab.h>
 #include <LibWeb/HTML/AudioPlayState.h>
@@ -45,7 +46,7 @@ namespace Web {
 
 class PageClient;
 
-class Page final : public JS::Cell {
+class WEB_API Page final : public JS::Cell {
     GC_CELL(Page, JS::Cell);
     GC_DECLARE_ALLOCATOR(Page);
 
@@ -419,9 +420,9 @@ protected:
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::Page::MediaContextMenu const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::Page::MediaContextMenu const&);
 
 template<>
-ErrorOr<Web::Page::MediaContextMenu> decode(Decoder&);
+WEB_API ErrorOr<Web::Page::MediaContextMenu> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/Painting/BackgroundPainting.h b/Libraries/LibWeb/Painting/BackgroundPainting.h
index 7928cccf19c..fd5bdd69850 100644
--- a/Libraries/LibWeb/Painting/BackgroundPainting.h
+++ b/Libraries/LibWeb/Painting/BackgroundPainting.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Painting/BorderPainting.h>
 
@@ -45,8 +46,8 @@ struct ResolvedBackground {
     Color color {};
 };
 
-ResolvedBackground resolve_background_layers(Vector<CSS::BackgroundLayerData> const& layers, PaintableBox const& paintable_box, Color background_color, CSSPixelRect const& border_rect, BorderRadiiData const& border_radii);
+WEB_API ResolvedBackground resolve_background_layers(Vector<CSS::BackgroundLayerData> const& layers, PaintableBox const& paintable_box, Color background_color, CSSPixelRect const& border_rect, BorderRadiiData const& border_radii);
 
-void paint_background(DisplayListRecordingContext&, PaintableBox const&, CSS::ImageRendering, ResolvedBackground resolved_background, BorderRadiiData const&);
+WEB_API void paint_background(DisplayListRecordingContext&, PaintableBox const&, CSS::ImageRendering, ResolvedBackground resolved_background, BorderRadiiData const&);
 
 }
diff --git a/Libraries/LibWeb/Painting/BackingStoreManager.h b/Libraries/LibWeb/Painting/BackingStoreManager.h
index ad34004b8d2..57a5053318d 100644
--- a/Libraries/LibWeb/Painting/BackingStoreManager.h
+++ b/Libraries/LibWeb/Painting/BackingStoreManager.h
@@ -6,11 +6,12 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/Navigable.h>
 
 namespace Web::Painting {
 
-class BackingStoreManager : public JS::Cell {
+class WEB_API BackingStoreManager : public JS::Cell {
     GC_CELL(BackingStoreManager, JS::Cell);
     GC_DECLARE_ALLOCATOR(BackingStoreManager);
 
diff --git a/Libraries/LibWeb/Painting/BorderPainting.h b/Libraries/LibWeb/Painting/BorderPainting.h
index c1df849dd63..fcfcc23c288 100644
--- a/Libraries/LibWeb/Painting/BorderPainting.h
+++ b/Libraries/LibWeb/Painting/BorderPainting.h
@@ -9,6 +9,7 @@
 
 #include <LibGfx/Forward.h>
 #include <LibWeb/CSS/ComputedValues.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Painting/BorderRadiiData.h>
 #include <LibWeb/Painting/BordersData.h>
@@ -16,10 +17,10 @@
 namespace Web::Painting {
 
 // Returns OptionalNone if there is no outline to paint.
-Optional<BordersData> borders_data_for_outline(Layout::Node const&, Color outline_color, CSS::OutlineStyle outline_style, CSSPixels outline_width);
+WEB_API Optional<BordersData> borders_data_for_outline(Layout::Node const&, Color outline_color, CSS::OutlineStyle outline_style, CSSPixels outline_width);
 
 void paint_border(DisplayListRecorder& painter, BorderEdge edge, DevicePixelRect const& rect, CornerRadius const& radius, CornerRadius const& opposite_radius, BordersDataDevicePixels const& borders_data, Gfx::Path&, bool last);
-void paint_all_borders(DisplayListRecorder& painter, DevicePixelRect const& border_rect, CornerRadii const& corner_radii, BordersDataDevicePixels const&);
+WEB_API void paint_all_borders(DisplayListRecorder& painter, DevicePixelRect const& border_rect, CornerRadii const& corner_radii, BordersDataDevicePixels const&);
 
 Gfx::Color border_color(BorderEdge edge, BordersDataDevicePixels const& borders_data);
 
diff --git a/Libraries/LibWeb/Painting/BorderRadiiData.h b/Libraries/LibWeb/Painting/BorderRadiiData.h
index a8cc8130f25..2826a8a18a0 100644
--- a/Libraries/LibWeb/Painting/BorderRadiiData.h
+++ b/Libraries/LibWeb/Painting/BorderRadiiData.h
@@ -8,6 +8,7 @@
 #pragma once
 
 #include <LibWeb/CSS/ComputedValues.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Painting {
 
@@ -21,7 +22,7 @@ struct CornerRadius {
     }
 };
 
-struct BorderRadiusData {
+struct WEB_API BorderRadiusData {
     CSSPixels horizontal_radius { 0 };
     CSSPixels vertical_radius { 0 };
 
diff --git a/Libraries/LibWeb/Painting/BorderRadiusCornerClipper.h b/Libraries/LibWeb/Painting/BorderRadiusCornerClipper.h
index 3a42c60f5b1..1157c0c38cf 100644
--- a/Libraries/LibWeb/Painting/BorderRadiusCornerClipper.h
+++ b/Libraries/LibWeb/Painting/BorderRadiusCornerClipper.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Painting/BorderPainting.h>
 
 namespace Web::Painting {
@@ -15,7 +16,7 @@ enum class CornerClip {
     Inside
 };
 
-struct ScopedCornerRadiusClip {
+struct WEB_API ScopedCornerRadiusClip {
     ScopedCornerRadiusClip(DisplayListRecordingContext& context, DevicePixelRect const& border_rect, BorderRadiiData const& border_radii, CornerClip corner_clip = CornerClip::Outside, bool do_apply = true);
 
     ~ScopedCornerRadiusClip();
diff --git a/Libraries/LibWeb/Painting/BordersData.h b/Libraries/LibWeb/Painting/BordersData.h
index a2e418d1152..b8e849266f3 100644
--- a/Libraries/LibWeb/Painting/BordersData.h
+++ b/Libraries/LibWeb/Painting/BordersData.h
@@ -10,6 +10,7 @@
 #include <LibGfx/Color.h>
 #include <LibWeb/CSS/ComputedValues.h>
 #include <LibWeb/CSS/Enums.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/PixelUnits.h>
 
 namespace Web::Painting {
@@ -54,7 +55,7 @@ struct BordersDataDevicePixels {
     }
 };
 
-struct BordersData {
+struct WEB_API BordersData {
     CSS::BorderData top;
     CSS::BorderData right;
     CSS::BorderData bottom;
diff --git a/Libraries/LibWeb/Painting/BoxModelMetrics.h b/Libraries/LibWeb/Painting/BoxModelMetrics.h
index afb1eb5b870..61e92db24aa 100644
--- a/Libraries/LibWeb/Painting/BoxModelMetrics.h
+++ b/Libraries/LibWeb/Painting/BoxModelMetrics.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/PixelUnits.h>
 
 namespace Web::Painting {
@@ -17,7 +18,7 @@ struct PixelBox {
     CSSPixels left { 0 };
 };
 
-struct BoxModelMetrics {
+struct WEB_API BoxModelMetrics {
 public:
     PixelBox margin;
     PixelBox padding;
diff --git a/Libraries/LibWeb/Painting/ClipFrame.h b/Libraries/LibWeb/Painting/ClipFrame.h
index 4b158c46f0d..93960f9e65c 100644
--- a/Libraries/LibWeb/Painting/ClipFrame.h
+++ b/Libraries/LibWeb/Painting/ClipFrame.h
@@ -6,6 +6,7 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Painting/BorderRadiiData.h>
 #include <LibWeb/Painting/ScrollFrame.h>
 #include <LibWeb/PixelUnits.h>
@@ -19,7 +20,7 @@ struct ClipRectWithScrollFrame {
     Optional<size_t> enclosing_scroll_frame_id;
 };
 
-struct ClipFrame : public AtomicRefCounted<ClipFrame> {
+struct WEB_API ClipFrame : public AtomicRefCounted<ClipFrame> {
     Vector<ClipRectWithScrollFrame> const& clip_rects() const { return m_clip_rects; }
     void add_clip_rect(CSSPixelRect rect, BorderRadiiData radii, RefPtr<ScrollFrame const> enclosing_scroll_frame);
 
diff --git a/Libraries/LibWeb/Painting/DisplayListRecorder.h b/Libraries/LibWeb/Painting/DisplayListRecorder.h
index eba70803871..a9be506723d 100644
--- a/Libraries/LibWeb/Painting/DisplayListRecorder.h
+++ b/Libraries/LibWeb/Painting/DisplayListRecorder.h
@@ -18,6 +18,7 @@
 #include <LibGfx/Point.h>
 #include <LibGfx/Rect.h>
 #include <LibGfx/ScalingMode.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Painting/BorderRadiiData.h>
 #include <LibWeb/Painting/BorderRadiusCornerClipper.h>
@@ -34,7 +35,7 @@ struct StackingContextTransform {
     Gfx::FloatMatrix4x4 matrix;
 };
 
-class DisplayListRecorder {
+class WEB_API DisplayListRecorder {
     AK_MAKE_NONCOPYABLE(DisplayListRecorder);
     AK_MAKE_NONMOVABLE(DisplayListRecorder);
 
diff --git a/Libraries/LibWeb/Painting/DisplayListRecordingContext.h b/Libraries/LibWeb/Painting/DisplayListRecordingContext.h
index 8c93dd86e66..700162b4b17 100644
--- a/Libraries/LibWeb/Painting/DisplayListRecordingContext.h
+++ b/Libraries/LibWeb/Painting/DisplayListRecordingContext.h
@@ -10,13 +10,14 @@
 #include <LibGfx/Forward.h>
 #include <LibGfx/Palette.h>
 #include <LibGfx/Rect.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Painting/DevicePixelConverter.h>
 #include <LibWeb/PixelUnits.h>
 
 namespace Web {
 
-class DisplayListRecordingContext {
+class WEB_API DisplayListRecordingContext {
 public:
     DisplayListRecordingContext(Painting::DisplayListRecorder& painter, Palette const& palette, double device_pixels_per_css_pixel);
 
diff --git a/Libraries/LibWeb/Painting/Paintable.h b/Libraries/LibWeb/Painting/Paintable.h
index 491ac9a6652..eed56045b8a 100644
--- a/Libraries/LibWeb/Painting/Paintable.h
+++ b/Libraries/LibWeb/Painting/Paintable.h
@@ -8,6 +8,7 @@
 
 #include <LibGC/Root.h>
 #include <LibWeb/CSS/ComputedValues.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/InvalidateDisplayList.h>
 #include <LibWeb/PixelUnits.h>
@@ -48,7 +49,7 @@ enum class HitTestType {
     TextCursor, // Clicking past the right/bottom edge of text will still hit the text
 };
 
-class Paintable
+class WEB_API Paintable
     : public JS::Cell
     , public TreeNode<Paintable> {
     GC_CELL(Paintable, JS::Cell);
@@ -190,6 +191,6 @@ inline bool Paintable::fast_is<PaintableWithLines>() const { return is_paintable
 template<>
 inline bool Paintable::fast_is<TextPaintable>() const { return is_text_paintable(); }
 
-Painting::BorderRadiiData normalize_border_radii_data(Layout::Node const& node, CSSPixelRect const& rect, CSS::BorderRadiusData const& top_left_radius, CSS::BorderRadiusData const& top_right_radius, CSS::BorderRadiusData const& bottom_right_radius, CSS::BorderRadiusData const& bottom_left_radius);
+WEB_API Painting::BorderRadiiData normalize_border_radii_data(Layout::Node const& node, CSSPixelRect const& rect, CSS::BorderRadiusData const& top_left_radius, CSS::BorderRadiusData const& top_right_radius, CSS::BorderRadiusData const& bottom_right_radius, CSS::BorderRadiusData const& bottom_left_radius);
 
 }
diff --git a/Libraries/LibWeb/Painting/PaintableBox.cpp b/Libraries/LibWeb/Painting/PaintableBox.cpp
index 20e5bfc69bc..02a4a740ec9 100644
--- a/Libraries/LibWeb/Painting/PaintableBox.cpp
+++ b/Libraries/LibWeb/Painting/PaintableBox.cpp
@@ -38,6 +38,11 @@ GC_DEFINE_ALLOCATOR(PaintableWithLines);
 
 bool g_paint_viewport_scrollbars = true;
 
+void set_paint_viewport_scrollbars(bool const enabled)
+{
+    g_paint_viewport_scrollbars = enabled;
+}
+
 GC::Ref<PaintableWithLines> PaintableWithLines::create(Layout::BlockContainer const& block_container)
 {
     return block_container.heap().allocate<PaintableWithLines>(block_container);
diff --git a/Libraries/LibWeb/Painting/PaintableBox.h b/Libraries/LibWeb/Painting/PaintableBox.h
index 12574483247..b1bf0e1668f 100644
--- a/Libraries/LibWeb/Painting/PaintableBox.h
+++ b/Libraries/LibWeb/Painting/PaintableBox.h
@@ -10,6 +10,7 @@
 #include <LibGfx/Bitmap.h>
 #include <LibGfx/ImmutableBitmap.h>
 #include <LibWeb/CSS/StyleValues/GridTrackSizeListStyleValue.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Layout/Box.h>
 #include <LibWeb/Painting/BackgroundPainting.h>
@@ -22,9 +23,9 @@
 
 namespace Web::Painting {
 
-extern bool g_paint_viewport_scrollbars;
+WEB_API void set_paint_viewport_scrollbars(bool enabled);
 
-class PaintableBox : public Paintable
+class WEB_API PaintableBox : public Paintable
     , public Weakable<PaintableBox> {
     GC_CELL(PaintableBox, Paintable);
 
diff --git a/Libraries/LibWeb/Painting/PaintableFragment.h b/Libraries/LibWeb/Painting/PaintableFragment.h
index b2ae0fcf294..be20ea1067a 100644
--- a/Libraries/LibWeb/Painting/PaintableFragment.h
+++ b/Libraries/LibWeb/Painting/PaintableFragment.h
@@ -8,13 +8,14 @@
 
 #include <AK/Utf16View.h>
 #include <LibGfx/TextLayout.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Layout/Node.h>
 #include <LibWeb/Painting/ShadowData.h>
 #include <LibWeb/PixelUnits.h>
 
 namespace Web::Painting {
 
-class PaintableFragment {
+class WEB_API PaintableFragment {
     friend class PaintableWithLines;
 
 public:
diff --git a/Libraries/LibWeb/Painting/SVGPathPaintable.h b/Libraries/LibWeb/Painting/SVGPathPaintable.h
index b779a83bdd0..b4b13b752e6 100644
--- a/Libraries/LibWeb/Painting/SVGPathPaintable.h
+++ b/Libraries/LibWeb/Painting/SVGPathPaintable.h
@@ -7,12 +7,13 @@
 #pragma once
 
 #include <LibGfx/Path.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Layout/SVGGraphicsBox.h>
 #include <LibWeb/Painting/SVGGraphicsPaintable.h>
 
 namespace Web::Painting {
 
-class SVGPathPaintable final : public SVGGraphicsPaintable {
+class WEB_API SVGPathPaintable final : public SVGGraphicsPaintable {
     GC_CELL(SVGPathPaintable, SVGGraphicsPaintable);
     GC_DECLARE_ALLOCATOR(SVGPathPaintable);
 
diff --git a/Libraries/LibWeb/Painting/ShadowPainting.h b/Libraries/LibWeb/Painting/ShadowPainting.h
index d68cc85a485..633535dd888 100644
--- a/Libraries/LibWeb/Painting/ShadowPainting.h
+++ b/Libraries/LibWeb/Painting/ShadowPainting.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <LibGfx/Color.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Painting/DisplayListRecordingContext.h>
 #include <LibWeb/Painting/PaintBoxShadowParams.h>
@@ -15,13 +16,13 @@
 
 namespace Web::Painting {
 
-void paint_box_shadow(
+WEB_API void paint_box_shadow(
     DisplayListRecordingContext&,
     CSSPixelRect const& bordered_content_rect,
     CSSPixelRect const& borderless_content_rect,
     BordersData const& borders_data,
     BorderRadiiData const&,
     Vector<ShadowData> const&);
-void paint_text_shadow(DisplayListRecordingContext&, PaintableFragment const&, Vector<ShadowData> const&);
+WEB_API void paint_text_shadow(DisplayListRecordingContext&, PaintableFragment const&, Vector<ShadowData> const&);
 
 }
diff --git a/Libraries/LibWeb/Painting/StackingContext.h b/Libraries/LibWeb/Painting/StackingContext.h
index 1ca87385c2e..df1be7e9dc8 100644
--- a/Libraries/LibWeb/Painting/StackingContext.h
+++ b/Libraries/LibWeb/Painting/StackingContext.h
@@ -8,11 +8,12 @@
 
 #include <AK/Vector.h>
 #include <LibGfx/Matrix4x4.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Painting/Paintable.h>
 
 namespace Web::Painting {
 
-class StackingContext {
+class WEB_API StackingContext {
     friend class ViewportPaintable;
 
 public:
diff --git a/Libraries/LibWeb/Painting/TableBordersPainting.h b/Libraries/LibWeb/Painting/TableBordersPainting.h
index 108dd005315..3343e24f530 100644
--- a/Libraries/LibWeb/Painting/TableBordersPainting.h
+++ b/Libraries/LibWeb/Painting/TableBordersPainting.h
@@ -6,8 +6,10 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
+
 namespace Web::Painting {
 
-void paint_table_borders(DisplayListRecordingContext&, PaintableBox const& table_paintable);
+WEB_API void paint_table_borders(DisplayListRecordingContext&, PaintableBox const& table_paintable);
 
 }
diff --git a/Libraries/LibWeb/Painting/ViewportPaintable.h b/Libraries/LibWeb/Painting/ViewportPaintable.h
index dcbf2ced34c..854a64cf092 100644
--- a/Libraries/LibWeb/Painting/ViewportPaintable.h
+++ b/Libraries/LibWeb/Painting/ViewportPaintable.h
@@ -7,12 +7,13 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Painting/PaintableBox.h>
 #include <LibWeb/Painting/ScrollState.h>
 
 namespace Web::Painting {
 
-class ViewportPaintable final : public PaintableWithLines {
+class WEB_API ViewportPaintable final : public PaintableWithLines {
     GC_CELL(ViewportPaintable, PaintableWithLines);
     GC_DECLARE_ALLOCATOR(ViewportPaintable);
 
diff --git a/Libraries/LibWeb/PermissionsPolicy/AutoplayAllowlist.h b/Libraries/LibWeb/PermissionsPolicy/AutoplayAllowlist.h
index 2c2929eec0b..2bd7795dd88 100644
--- a/Libraries/LibWeb/PermissionsPolicy/AutoplayAllowlist.h
+++ b/Libraries/LibWeb/PermissionsPolicy/AutoplayAllowlist.h
@@ -10,12 +10,13 @@
 #include <AK/Variant.h>
 #include <AK/Vector.h>
 #include <LibURL/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/PermissionsPolicy/Decision.h>
 
 namespace Web::PermissionsPolicy {
 
-class AutoplayAllowlist {
+class WEB_API AutoplayAllowlist {
 public:
     static AutoplayAllowlist& the();
 
diff --git a/Libraries/LibWeb/PixelUnits.h b/Libraries/LibWeb/PixelUnits.h
index 56029327394..d99e8155f65 100644
--- a/Libraries/LibWeb/PixelUnits.h
+++ b/Libraries/LibWeb/PixelUnits.h
@@ -16,6 +16,7 @@
 #include <LibGfx/Forward.h>
 #include <LibGfx/Rect.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 #include <math.h>
 
 namespace Web {
@@ -56,7 +57,7 @@ class CSSPixelFraction;
 
 /// CSSPixels: A position or length in CSS "reference pixels", independent of zoom or screen DPI.
 /// See https://www.w3.org/TR/css-values-3/#reference-pixel
-class CSSPixels {
+class WEB_API CSSPixels {
 public:
     static constexpr i32 fractional_bits = 6;
     static constexpr i32 fixed_point_denominator = 1 << fractional_bits;
@@ -529,23 +530,23 @@ struct Formatter<Web::DevicePixels> : Formatter<Web::DevicePixels::Type> {
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder& encoder, Web::DevicePixels const& value);
+WEB_API ErrorOr<void> encode(Encoder& encoder, Web::DevicePixels const& value);
 template<>
-ErrorOr<Web::DevicePixels> decode(Decoder& decoder);
+WEB_API ErrorOr<Web::DevicePixels> decode(Decoder& decoder);
 
 template<>
-ErrorOr<void> encode(Encoder& encoder, Web::DevicePixelPoint const& value);
+WEB_API ErrorOr<void> encode(Encoder& encoder, Web::DevicePixelPoint const& value);
 template<>
-ErrorOr<Web::DevicePixelPoint> decode(Decoder& decoder);
+WEB_API ErrorOr<Web::DevicePixelPoint> decode(Decoder& decoder);
 
 template<>
-ErrorOr<void> encode(Encoder& encoder, Web::DevicePixelSize const& value);
+WEB_API ErrorOr<void> encode(Encoder& encoder, Web::DevicePixelSize const& value);
 template<>
-ErrorOr<Web::DevicePixelSize> decode(Decoder& decoder);
+WEB_API ErrorOr<Web::DevicePixelSize> decode(Decoder& decoder);
 
 template<>
-ErrorOr<void> encode(Encoder& encoder, Web::DevicePixelRect const& value);
+WEB_API ErrorOr<void> encode(Encoder& encoder, Web::DevicePixelRect const& value);
 template<>
-ErrorOr<Web::DevicePixelRect> decode(Decoder& decoder);
+WEB_API ErrorOr<Web::DevicePixelRect> decode(Decoder& decoder);
 
 }
diff --git a/Libraries/LibWeb/Platform/AudioCodecPlugin.h b/Libraries/LibWeb/Platform/AudioCodecPlugin.h
index 85a2a31a5f5..4863a904f14 100644
--- a/Libraries/LibWeb/Platform/AudioCodecPlugin.h
+++ b/Libraries/LibWeb/Platform/AudioCodecPlugin.h
@@ -12,10 +12,11 @@
 #include <AK/NonnullRefPtr.h>
 #include <AK/Weakable.h>
 #include <LibMedia/Audio/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Platform {
 
-class AudioCodecPlugin : public Weakable<AudioCodecPlugin> {
+class WEB_API AudioCodecPlugin : public Weakable<AudioCodecPlugin> {
 public:
     using AudioCodecPluginCreator = Function<ErrorOr<NonnullOwnPtr<AudioCodecPlugin>>(NonnullRefPtr<Audio::Loader>)>;
 
diff --git a/Libraries/LibWeb/Platform/AudioCodecPluginAgnostic.h b/Libraries/LibWeb/Platform/AudioCodecPluginAgnostic.h
index 31c2bafac2b..c416e05eb0c 100644
--- a/Libraries/LibWeb/Platform/AudioCodecPluginAgnostic.h
+++ b/Libraries/LibWeb/Platform/AudioCodecPluginAgnostic.h
@@ -8,11 +8,12 @@
 
 #include <LibCore/Timer.h>
 #include <LibMedia/Audio/PlaybackStream.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Platform/AudioCodecPlugin.h>
 
 namespace Web::Platform {
 
-class AudioCodecPluginAgnostic final : public AudioCodecPlugin {
+class WEB_API AudioCodecPluginAgnostic final : public AudioCodecPlugin {
 public:
     static ErrorOr<NonnullOwnPtr<AudioCodecPluginAgnostic>> create(NonnullRefPtr<Audio::Loader> const&);
 
diff --git a/Libraries/LibWeb/Platform/EventLoopPlugin.h b/Libraries/LibWeb/Platform/EventLoopPlugin.h
index 4ec72a17d9c..99b8c5004b5 100644
--- a/Libraries/LibWeb/Platform/EventLoopPlugin.h
+++ b/Libraries/LibWeb/Platform/EventLoopPlugin.h
@@ -9,11 +9,12 @@
 #include <AK/Forward.h>
 #include <LibGC/Function.h>
 #include <LibGC/Ptr.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Platform {
 
-class EventLoopPlugin {
+class WEB_API EventLoopPlugin {
 public:
     static EventLoopPlugin& the();
     static void install(EventLoopPlugin&);
diff --git a/Libraries/LibWeb/Platform/EventLoopPluginSerenity.h b/Libraries/LibWeb/Platform/EventLoopPluginSerenity.h
index 0a88669a04b..945f1726029 100644
--- a/Libraries/LibWeb/Platform/EventLoopPluginSerenity.h
+++ b/Libraries/LibWeb/Platform/EventLoopPluginSerenity.h
@@ -6,11 +6,12 @@
 
 #pragma once
 
+#include <LibWeb/Export.h>
 #include <LibWeb/Platform/EventLoopPlugin.h>
 
 namespace Web::Platform {
 
-class EventLoopPluginSerenity final : public Web::Platform::EventLoopPlugin {
+class WEB_API EventLoopPluginSerenity final : public Web::Platform::EventLoopPlugin {
 public:
     EventLoopPluginSerenity();
     virtual ~EventLoopPluginSerenity() override;
diff --git a/Libraries/LibWeb/Platform/FontPlugin.h b/Libraries/LibWeb/Platform/FontPlugin.h
index 270eb6c411f..5561da06405 100644
--- a/Libraries/LibWeb/Platform/FontPlugin.h
+++ b/Libraries/LibWeb/Platform/FontPlugin.h
@@ -8,6 +8,7 @@
 
 #include <AK/Forward.h>
 #include <LibGfx/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Platform {
 
@@ -24,7 +25,7 @@ enum class GenericFont {
     __Count,
 };
 
-class FontPlugin {
+class WEB_API FontPlugin {
 public:
     static FontPlugin& the();
     static void install(FontPlugin&);
diff --git a/Libraries/LibWeb/Platform/ImageCodecPlugin.h b/Libraries/LibWeb/Platform/ImageCodecPlugin.h
index 9cd680b6ec4..ba90a164b8b 100644
--- a/Libraries/LibWeb/Platform/ImageCodecPlugin.h
+++ b/Libraries/LibWeb/Platform/ImageCodecPlugin.h
@@ -12,6 +12,7 @@
 #include <LibCore/Promise.h>
 #include <LibGfx/ColorSpace.h>
 #include <LibGfx/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::Platform {
 
@@ -27,7 +28,7 @@ struct DecodedImage {
     Gfx::ColorSpace color_space;
 };
 
-class ImageCodecPlugin {
+class WEB_API ImageCodecPlugin {
 public:
     static ImageCodecPlugin& the();
     static void install(ImageCodecPlugin&);
diff --git a/Libraries/LibWeb/ResourceTiming/PerformanceResourceTiming.h b/Libraries/LibWeb/ResourceTiming/PerformanceResourceTiming.h
index 7bc6cac944b..699d940c0af 100644
--- a/Libraries/LibWeb/ResourceTiming/PerformanceResourceTiming.h
+++ b/Libraries/LibWeb/ResourceTiming/PerformanceResourceTiming.h
@@ -8,6 +8,7 @@
 
 #include <AK/FlyString.h>
 #include <LibWeb/Bindings/PerformanceResourceTimingPrototype.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Requests.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Responses.h>
 #include <LibWeb/PerformanceTimeline/PerformanceEntry.h>
@@ -15,7 +16,7 @@
 namespace Web::ResourceTiming {
 
 // https://w3c.github.io/resource-timing/#dom-performanceresourcetiming
-class PerformanceResourceTiming : public PerformanceTimeline::PerformanceEntry {
+class WEB_API PerformanceResourceTiming : public PerformanceTimeline::PerformanceEntry {
     WEB_PLATFORM_OBJECT(PerformanceResourceTiming, PerformanceTimeline::PerformanceEntry);
     GC_DECLARE_ALLOCATOR(PerformanceResourceTiming);
 
diff --git a/Libraries/LibWeb/SRI/SRI.h b/Libraries/LibWeb/SRI/SRI.h
index f9e19474c12..64e16695ad4 100644
--- a/Libraries/LibWeb/SRI/SRI.h
+++ b/Libraries/LibWeb/SRI/SRI.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/String.h>
+#include <LibWeb/Export.h>
 
 namespace Web::SRI {
 
@@ -18,8 +19,8 @@ struct Metadata {
 };
 
 ErrorOr<String> apply_algorithm_to_bytes(StringView algorithm, ByteBuffer const& bytes);
-ErrorOr<Vector<Metadata>> parse_metadata(StringView metadata);
+WEB_API ErrorOr<Vector<Metadata>> parse_metadata(StringView metadata);
 ErrorOr<Vector<Metadata>> get_strongest_metadata_from_set(Vector<Metadata> const& set);
-ErrorOr<bool> do_bytes_match_metadata_list(ByteBuffer const& bytes, StringView metadata_list);
+WEB_API ErrorOr<bool> do_bytes_match_metadata_list(ByteBuffer const& bytes, StringView metadata_list);
 
 }
diff --git a/Libraries/LibWeb/SVG/AttributeParser.h b/Libraries/LibWeb/SVG/AttributeParser.h
index 13419c5ad67..ae836c19a87 100644
--- a/Libraries/LibWeb/SVG/AttributeParser.h
+++ b/Libraries/LibWeb/SVG/AttributeParser.h
@@ -12,6 +12,7 @@
 #include <AK/Variant.h>
 #include <AK/Vector.h>
 #include <LibGfx/Point.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/SVG/Path.h>
 
 namespace Web::SVG {
@@ -86,7 +87,7 @@ enum class SpreadMethod {
     Reflect
 };
 
-class NumberPercentage {
+class WEB_API NumberPercentage {
 public:
     NumberPercentage(float value, bool is_percentage)
         : m_value(is_percentage ? value / 100 : value)
@@ -126,7 +127,7 @@ enum class TextAnchor {
     End
 };
 
-class AttributeParser final {
+class WEB_API AttributeParser final {
 public:
     ~AttributeParser() = default;
 
diff --git a/Libraries/LibWeb/SVG/SVGAnimatedString.h b/Libraries/LibWeb/SVG/SVGAnimatedString.h
index eb365f7faea..31a453f8f95 100644
--- a/Libraries/LibWeb/SVG/SVGAnimatedString.h
+++ b/Libraries/LibWeb/SVG/SVGAnimatedString.h
@@ -8,11 +8,12 @@
 
 #include <AK/FlyString.h>
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 
 namespace Web::SVG {
 
 // https://svgwg.org/svg2-draft/types.html#InterfaceSVGAnimatedString
-class SVGAnimatedString final : public Bindings::PlatformObject {
+class WEB_API SVGAnimatedString final : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(SVGAnimatedString, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(SVGAnimatedString);
 
diff --git a/Libraries/LibWeb/SVG/SVGElement.h b/Libraries/LibWeb/SVG/SVGElement.h
index 54e98980894..781e70f583f 100644
--- a/Libraries/LibWeb/SVG/SVGElement.h
+++ b/Libraries/LibWeb/SVG/SVGElement.h
@@ -8,12 +8,13 @@
 
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/DOM/Element.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/HTMLOrSVGElement.h>
 #include <LibWeb/SVG/SVGAnimatedString.h>
 
 namespace Web::SVG {
 
-class SVGElement
+class WEB_API SVGElement
     : public DOM::Element
     , public HTML::GlobalEventHandlers
     , public HTML::HTMLOrSVGElement<SVGElement> {
diff --git a/Libraries/LibWeb/SVG/SVGGraphicsElement.h b/Libraries/LibWeb/SVG/SVGGraphicsElement.h
index 6a8d4580b93..1a4d8904415 100644
--- a/Libraries/LibWeb/SVG/SVGGraphicsElement.h
+++ b/Libraries/LibWeb/SVG/SVGGraphicsElement.h
@@ -10,6 +10,7 @@
 #include <LibGfx/PaintStyle.h>
 #include <LibWeb/CSS/URL.h>
 #include <LibWeb/DOM/Node.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/SVG/AttributeParser.h>
 #include <LibWeb/SVG/SVGAnimatedTransformList.h>
 #include <LibWeb/SVG/SVGElement.h>
@@ -26,7 +27,7 @@ struct SVGBoundingBoxOptions {
     bool clipped { false };
 };
 
-class SVGGraphicsElement : public SVGElement {
+class WEB_API SVGGraphicsElement : public SVGElement {
     WEB_PLATFORM_OBJECT(SVGGraphicsElement, SVGElement);
 
 public:
diff --git a/Libraries/LibWeb/SecureContexts/AbstractOperations.h b/Libraries/LibWeb/SecureContexts/AbstractOperations.h
index d5360b980c3..08ed7c208e9 100644
--- a/Libraries/LibWeb/SecureContexts/AbstractOperations.h
+++ b/Libraries/LibWeb/SecureContexts/AbstractOperations.h
@@ -8,6 +8,7 @@
 
 #include <AK/Forward.h>
 #include <LibURL/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::SecureContexts {
@@ -18,6 +19,6 @@ enum class Trustworthiness {
 };
 
 [[nodiscard]] Trustworthiness is_origin_potentially_trustworthy(URL::Origin const&);
-[[nodiscard]] Trustworthiness is_url_potentially_trustworthy(URL::URL const&);
+[[nodiscard]] WEB_API Trustworthiness is_url_potentially_trustworthy(URL::URL const&);
 
 }
diff --git a/Libraries/LibWeb/Selection/Selection.h b/Libraries/LibWeb/Selection/Selection.h
index 44457fff72f..0b947061962 100644
--- a/Libraries/LibWeb/Selection/Selection.h
+++ b/Libraries/LibWeb/Selection/Selection.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::Selection {
 
-class Selection final : public Bindings::PlatformObject {
+class WEB_API Selection final : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(Selection, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(Selection);
 
diff --git a/Libraries/LibWeb/Streams/AbstractOperations.h b/Libraries/LibWeb/Streams/AbstractOperations.h
index 7f17ee8c04d..f6be2fa492f 100644
--- a/Libraries/LibWeb/Streams/AbstractOperations.h
+++ b/Libraries/LibWeb/Streams/AbstractOperations.h
@@ -11,6 +11,7 @@
 #pragma once
 
 #include <LibGC/Ptr.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/Streams/Algorithms.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
@@ -18,23 +19,23 @@
 namespace Web::Streams {
 
 // 7.4. Abstract operations, https://streams.spec.whatwg.org/#qs-abstract-ops
-WebIDL::ExceptionOr<double> extract_high_water_mark(QueuingStrategy const&, double default_hwm);
-GC::Ref<SizeAlgorithm> extract_size_algorithm(JS::VM&, QueuingStrategy const&);
+WEB_API WebIDL::ExceptionOr<double> extract_high_water_mark(QueuingStrategy const&, double default_hwm);
+WEB_API GC::Ref<SizeAlgorithm> extract_size_algorithm(JS::VM&, QueuingStrategy const&);
 
 // 8.2. Transferable streams, https://streams.spec.whatwg.org/#transferrable-streams
 void cross_realm_transform_send_error(JS::Realm&, HTML::MessagePort&, JS::Value error);
 WebIDL::ExceptionOr<void> pack_and_post_message(JS::Realm&, HTML::MessagePort&, StringView type, JS::Value value);
 WebIDL::ExceptionOr<void> pack_and_post_message_handling_error(JS::Realm&, HTML::MessagePort&, StringView type, JS::Value value);
-void set_up_cross_realm_transform_readable(JS::Realm&, ReadableStream&, HTML::MessagePort&);
-void set_up_cross_realm_transform_writable(JS::Realm&, WritableStream&, HTML::MessagePort&);
+WEB_API void set_up_cross_realm_transform_readable(JS::Realm&, ReadableStream&, HTML::MessagePort&);
+WEB_API void set_up_cross_realm_transform_writable(JS::Realm&, WritableStream&, HTML::MessagePort&);
 
 // 8.3. Miscellaneous, https://streams.spec.whatwg.org/#misc-abstract-ops
-bool can_transfer_array_buffer(JS::ArrayBuffer const& array_buffer);
-bool is_non_negative_number(JS::Value);
-WebIDL::ExceptionOr<GC::Ref<JS::ArrayBuffer>> transfer_array_buffer(JS::Realm& realm, JS::ArrayBuffer& buffer);
-WebIDL::ExceptionOr<JS::Value> clone_as_uint8_array(JS::Realm&, WebIDL::ArrayBufferView&);
-WebIDL::ExceptionOr<JS::Value> structured_clone(JS::Realm&, JS::Value value);
-bool can_copy_data_block_bytes_buffer(JS::ArrayBuffer const& to_buffer, u64 to_index, JS::ArrayBuffer const& from_buffer, u64 from_index, u64 count);
+WEB_API bool can_transfer_array_buffer(JS::ArrayBuffer const& array_buffer);
+WEB_API bool is_non_negative_number(JS::Value);
+WEB_API WebIDL::ExceptionOr<GC::Ref<JS::ArrayBuffer>> transfer_array_buffer(JS::Realm& realm, JS::ArrayBuffer& buffer);
+WEB_API WebIDL::ExceptionOr<JS::Value> clone_as_uint8_array(JS::Realm&, WebIDL::ArrayBufferView&);
+WEB_API WebIDL::ExceptionOr<JS::Value> structured_clone(JS::Realm&, JS::Value value);
+WEB_API bool can_copy_data_block_bytes_buffer(JS::ArrayBuffer const& to_buffer, u64 to_index, JS::ArrayBuffer const& from_buffer, u64 from_index, u64 count);
 
 // 8.1. Queue-with-sizes, https://streams.spec.whatwg.org/#queue-with-sizes
 
diff --git a/Libraries/LibWeb/Streams/Transformer.h b/Libraries/LibWeb/Streams/Transformer.h
index 565abb9631a..050956ffd3c 100644
--- a/Libraries/LibWeb/Streams/Transformer.h
+++ b/Libraries/LibWeb/Streams/Transformer.h
@@ -8,12 +8,13 @@
 
 #include <LibGC/Root.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Streams {
 
 // https://streams.spec.whatwg.org/#dictdef-transformer
-struct Transformer {
+struct WEB_API Transformer {
     // https://streams.spec.whatwg.org/#dom-transformer-start
     GC::Root<WebIDL::CallbackType> start;
     // https://streams.spec.whatwg.org/#dom-transformer-transform
diff --git a/Libraries/LibWeb/Streams/UnderlyingSink.h b/Libraries/LibWeb/Streams/UnderlyingSink.h
index 90e20bddbab..b1411252bd3 100644
--- a/Libraries/LibWeb/Streams/UnderlyingSink.h
+++ b/Libraries/LibWeb/Streams/UnderlyingSink.h
@@ -8,12 +8,13 @@
 
 #include <AK/Forward.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::Streams {
 
 // https://streams.spec.whatwg.org/#dictdef-underlyingsink
-struct UnderlyingSink {
+struct WEB_API UnderlyingSink {
     GC::Root<WebIDL::CallbackType> start;
     GC::Root<WebIDL::CallbackType> write;
     GC::Root<WebIDL::CallbackType> close;
diff --git a/Libraries/LibWeb/Streams/UnderlyingSource.h b/Libraries/LibWeb/Streams/UnderlyingSource.h
index 36d7af54974..f316c8d87f9 100644
--- a/Libraries/LibWeb/Streams/UnderlyingSource.h
+++ b/Libraries/LibWeb/Streams/UnderlyingSource.h
@@ -9,6 +9,7 @@
 #include <AK/Forward.h>
 #include <LibJS/Forward.h>
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebIDL/Promise.h>
 
@@ -18,7 +19,7 @@ enum class ReadableStreamType {
     Bytes
 };
 
-struct UnderlyingSource {
+struct WEB_API UnderlyingSource {
     GC::Root<WebIDL::CallbackType> start;
     GC::Root<WebIDL::CallbackType> pull;
     GC::Root<WebIDL::CallbackType> cancel;
diff --git a/Libraries/LibWeb/TreeNode.h b/Libraries/LibWeb/TreeNode.h
index 91d5e3b7795..78286ef7bbc 100644
--- a/Libraries/LibWeb/TreeNode.h
+++ b/Libraries/LibWeb/TreeNode.h
@@ -47,7 +47,7 @@ TraversalDecision traverse_preorder(T root, Callback callback)
 }
 
 template<typename T>
-class TreeNode {
+class WEB_API TreeNode {
 public:
     T* parent() { return m_parent; }
     T const* parent() const { return m_parent; }
diff --git a/Libraries/LibWeb/UIEvents/EventNames.h b/Libraries/LibWeb/UIEvents/EventNames.h
index 14fdc4d4e8c..f91f9e9ce49 100644
--- a/Libraries/LibWeb/UIEvents/EventNames.h
+++ b/Libraries/LibWeb/UIEvents/EventNames.h
@@ -9,6 +9,7 @@
 #pragma once
 
 #include <AK/FlyString.h>
+#include <LibWeb/Export.h>
 
 namespace Web::UIEvents::EventNames {
 
@@ -43,7 +44,7 @@ namespace Web::UIEvents::EventNames {
     __ENUMERATE_UI_EVENT(resize)             \
     __ENUMERATE_UI_EVENT(wheel)
 
-#define __ENUMERATE_UI_EVENT(name) extern FlyString name;
+#define __ENUMERATE_UI_EVENT(name) extern WEB_API FlyString name;
 ENUMERATE_UI_EVENTS
 #undef __ENUMERATE_UI_EVENT
 
diff --git a/Libraries/LibWeb/UIEvents/MouseEvent.h b/Libraries/LibWeb/UIEvents/MouseEvent.h
index f12bd0e0de7..f7f5a4cf53b 100644
--- a/Libraries/LibWeb/UIEvents/MouseEvent.h
+++ b/Libraries/LibWeb/UIEvents/MouseEvent.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/TypeCasts.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/PixelUnits.h>
 #include <LibWeb/UIEvents/EventModifier.h>
 #include <LibWeb/UIEvents/UIEvent.h>
@@ -25,7 +26,7 @@ struct MouseEventInit : public EventModifierInit {
     GC::Ptr<DOM::EventTarget> related_target = nullptr;
 };
 
-class MouseEvent : public UIEvent {
+class WEB_API MouseEvent : public UIEvent {
     WEB_PLATFORM_OBJECT(MouseEvent, UIEvent);
     GC_DECLARE_ALLOCATOR(MouseEvent);
 
diff --git a/Libraries/LibWeb/UIEvents/UIEvent.h b/Libraries/LibWeb/UIEvents/UIEvent.h
index 27446532988..42ac73138c2 100644
--- a/Libraries/LibWeb/UIEvents/UIEvent.h
+++ b/Libraries/LibWeb/UIEvents/UIEvent.h
@@ -8,6 +8,7 @@
 
 #include <AK/RefPtr.h>
 #include <LibWeb/DOM/Event.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/Window.h>
 
 namespace Web::UIEvents {
@@ -17,7 +18,7 @@ struct UIEventInit : public DOM::EventInit {
     int detail { 0 };
 };
 
-class UIEvent : public DOM::Event {
+class WEB_API UIEvent : public DOM::Event {
     WEB_PLATFORM_OBJECT(UIEvent, DOM::Event);
     GC_DECLARE_ALLOCATOR(UIEvent);
 
diff --git a/Libraries/LibWeb/WebAssembly/WebAssembly.h b/Libraries/LibWeb/WebAssembly/WebAssembly.h
index 6f89ef52769..453dab6fc42 100644
--- a/Libraries/LibWeb/WebAssembly/WebAssembly.h
+++ b/Libraries/LibWeb/WebAssembly/WebAssembly.h
@@ -15,21 +15,22 @@
 #include <LibJS/Runtime/PrototypeObject.h>
 #include <LibJS/Runtime/Value.h>
 #include <LibWasm/AbstractMachine/AbstractMachine.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::WebAssembly {
 
-void visit_edges(JS::Object&, JS::Cell::Visitor&);
-void finalize(JS::Object&);
-void initialize(JS::Object&, JS::Realm&);
+WEB_API void visit_edges(JS::Object&, JS::Cell::Visitor&);
+WEB_API void finalize(JS::Object&);
+WEB_API void initialize(JS::Object&, JS::Realm&);
 
-bool validate(JS::VM&, GC::Root<WebIDL::BufferSource>& bytes);
-WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> compile(JS::VM&, GC::Root<WebIDL::BufferSource>& bytes);
-WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> compile_streaming(JS::VM&, GC::Root<WebIDL::Promise> source);
+WEB_API bool validate(JS::VM&, GC::Root<WebIDL::BufferSource>& bytes);
+WEB_API WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> compile(JS::VM&, GC::Root<WebIDL::BufferSource>& bytes);
+WEB_API WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> compile_streaming(JS::VM&, GC::Root<WebIDL::Promise> source);
 
-WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> instantiate(JS::VM&, GC::Root<WebIDL::BufferSource>& bytes, Optional<GC::Root<JS::Object>>& import_object);
-WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> instantiate(JS::VM&, Module const& module_object, Optional<GC::Root<JS::Object>>& import_object);
-WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> instantiate_streaming(JS::VM&, GC::Root<WebIDL::Promise> source, Optional<GC::Root<JS::Object>>& import_object);
+WEB_API WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> instantiate(JS::VM&, GC::Root<WebIDL::BufferSource>& bytes, Optional<GC::Root<JS::Object>>& import_object);
+WEB_API WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> instantiate(JS::VM&, Module const& module_object, Optional<GC::Root<JS::Object>>& import_object);
+WEB_API WebIDL::ExceptionOr<GC::Ref<WebIDL::Promise>> instantiate_streaming(JS::VM&, GC::Root<WebIDL::Promise> source, Optional<GC::Root<JS::Object>>& import_object);
 
 namespace Detail {
 
@@ -122,7 +123,7 @@ extern HashMap<GC::Ptr<JS::Object>, WebAssemblyCache> s_caches;
 //       our implementation uses this fact in places, but for the purposes of wasm returning
 //       *some* kind of error, named e.g. 'WebAssembly.RuntimeError', this is sufficient.
 #define DECLARE_WASM_NATIVE_ERROR(ClassName, FullClassName, snake_name, PrototypeName, ConstructorName) \
-    class ClassName final : public JS::Error {                                                          \
+    class WEB_API ClassName final : public JS::Error {                                                  \
         JS_OBJECT(ClassName, Error);                                                                    \
         GC_DECLARE_ALLOCATOR(ClassName);                                                                \
                                                                                                         \
diff --git a/Libraries/LibWeb/WebDriver/Actions.h b/Libraries/LibWeb/WebDriver/Actions.h
index 881ba41f499..d9ea6468ceb 100644
--- a/Libraries/LibWeb/WebDriver/Actions.h
+++ b/Libraries/LibWeb/WebDriver/Actions.h
@@ -13,6 +13,7 @@
 #include <AK/Vector.h>
 #include <LibGC/Function.h>
 #include <LibGC/Ptr.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/PixelUnits.h>
 #include <LibWeb/UIEvents/MouseButton.h>
@@ -23,7 +24,7 @@
 namespace Web::WebDriver {
 
 // https://w3c.github.io/webdriver/#dfn-action-object
-struct ActionObject {
+struct WEB_API ActionObject {
     enum class Subtype {
         Pause,
         KeyUp,
@@ -126,12 +127,12 @@ struct ActionsOptions {
 
 using OnActionsComplete = GC::Ref<GC::Function<void(Web::WebDriver::Response)>>;
 
-ErrorOr<Vector<Vector<ActionObject>>, WebDriver::Error> extract_an_action_sequence(InputState&, JsonValue const&, ActionsOptions const&);
+WEB_API ErrorOr<Vector<Vector<ActionObject>>, WebDriver::Error> extract_an_action_sequence(InputState&, JsonValue const&, ActionsOptions const&);
 
-void wait_for_an_action_queue_token(InputState&);
-GC::Ref<JS::Cell> dispatch_actions(InputState&, Vector<Vector<ActionObject>>, HTML::BrowsingContext&, ActionsOptions, OnActionsComplete);
+WEB_API void wait_for_an_action_queue_token(InputState&);
+WEB_API GC::Ref<JS::Cell> dispatch_actions(InputState&, Vector<Vector<ActionObject>>, HTML::BrowsingContext&, ActionsOptions, OnActionsComplete);
 ErrorOr<void, WebDriver::Error> dispatch_tick_actions(InputState&, ReadonlySpan<ActionObject>, AK::Duration, HTML::BrowsingContext&, ActionsOptions const&);
-GC::Ref<JS::Cell> dispatch_list_of_actions(InputState&, Vector<ActionObject>, HTML::BrowsingContext&, ActionsOptions, OnActionsComplete);
-GC::Ref<JS::Cell> dispatch_actions_for_a_string(Web::WebDriver::InputState&, String const& input_id, Web::WebDriver::InputSource&, StringView text, Web::HTML::BrowsingContext&, Web::WebDriver::OnActionsComplete);
+WEB_API GC::Ref<JS::Cell> dispatch_list_of_actions(InputState&, Vector<ActionObject>, HTML::BrowsingContext&, ActionsOptions, OnActionsComplete);
+WEB_API GC::Ref<JS::Cell> dispatch_actions_for_a_string(Web::WebDriver::InputState&, String const& input_id, Web::WebDriver::InputSource&, StringView text, Web::HTML::BrowsingContext&, Web::WebDriver::OnActionsComplete);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/Capabilities.h b/Libraries/LibWeb/WebDriver/Capabilities.h
index e8e4b5d8f5b..cd73aaee516 100644
--- a/Libraries/LibWeb/WebDriver/Capabilities.h
+++ b/Libraries/LibWeb/WebDriver/Capabilities.h
@@ -9,6 +9,7 @@
 #include <AK/EnumBits.h>
 #include <AK/Forward.h>
 #include <AK/StringView.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebDriver/Response.h>
 
 namespace Web::WebDriver {
@@ -41,14 +42,14 @@ enum class InterfaceMode {
     Graphical,
     Headless,
 };
-void set_default_interface_mode(InterfaceMode);
+WEB_API void set_default_interface_mode(InterfaceMode);
 
-struct LadybirdOptions {
+struct WEB_API LadybirdOptions {
     explicit LadybirdOptions(JsonObject const& capabilities);
 
     bool headless { false };
 };
 
-Response process_capabilities(JsonValue const& parameters, SessionFlags flags);
+WEB_API Response process_capabilities(JsonValue const& parameters, SessionFlags flags);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/Client.h b/Libraries/LibWeb/WebDriver/Client.h
index 0c5015f2ee8..b34ea19d741 100644
--- a/Libraries/LibWeb/WebDriver/Client.h
+++ b/Libraries/LibWeb/WebDriver/Client.h
@@ -17,6 +17,7 @@
 #include <LibCore/Socket.h>
 #include <LibHTTP/Forward.h>
 #include <LibHTTP/HttpRequest.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebDriver/Error.h>
 #include <LibWeb/WebDriver/Response.h>
 
@@ -24,7 +25,7 @@ namespace Web::WebDriver {
 
 using Parameters = Vector<String>;
 
-class Client : public Core::EventReceiver {
+class WEB_API Client : public Core::EventReceiver {
     C_OBJECT_ABSTRACT(Client);
 
 public:
diff --git a/Libraries/LibWeb/WebDriver/Contexts.h b/Libraries/LibWeb/WebDriver/Contexts.h
index e18416659f6..6de5c71e000 100644
--- a/Libraries/LibWeb/WebDriver/Contexts.h
+++ b/Libraries/LibWeb/WebDriver/Contexts.h
@@ -9,6 +9,7 @@
 #include <AK/Forward.h>
 #include <AK/StringView.h>
 #include <LibJS/Runtime/Value.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebDriver/Error.h>
 
@@ -22,6 +23,6 @@ ErrorOr<GC::Ref<HTML::WindowProxy>, WebDriver::Error> deserialize_web_frame(JS::
 bool represents_a_web_window(JS::Value);
 ErrorOr<GC::Ref<HTML::WindowProxy>, WebDriver::Error> deserialize_web_window(JS::Object const&);
 
-ErrorOr<void, WebDriver::Error> ensure_browsing_context_is_open(GC::Ptr<HTML::BrowsingContext>);
+WEB_API ErrorOr<void, WebDriver::Error> ensure_browsing_context_is_open(GC::Ptr<HTML::BrowsingContext>);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/ElementLocationStrategies.h b/Libraries/LibWeb/WebDriver/ElementLocationStrategies.h
index 8b086724b35..28187eadd54 100644
--- a/Libraries/LibWeb/WebDriver/ElementLocationStrategies.h
+++ b/Libraries/LibWeb/WebDriver/ElementLocationStrategies.h
@@ -9,6 +9,7 @@
 
 #include <LibGC/Ptr.h>
 #include <LibWeb/DOM/NodeList.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebDriver/Error.h>
 
@@ -23,7 +24,7 @@ enum class LocationStrategy {
     XPath,
 };
 
-Optional<LocationStrategy> location_strategy_from_string(StringView type);
-ErrorOr<GC::Ref<DOM::NodeList>, Error> invoke_location_strategy(LocationStrategy type, DOM::ParentNode& start_node, StringView selector);
+WEB_API Optional<LocationStrategy> location_strategy_from_string(StringView type);
+WEB_API ErrorOr<GC::Ref<DOM::NodeList>, Error> invoke_location_strategy(LocationStrategy type, DOM::ParentNode& start_node, StringView selector);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/ElementReference.h b/Libraries/LibWeb/WebDriver/ElementReference.h
index 25bf4023439..b0b967fc085 100644
--- a/Libraries/LibWeb/WebDriver/ElementReference.h
+++ b/Libraries/LibWeb/WebDriver/ElementReference.h
@@ -12,6 +12,7 @@
 #include <LibGC/Ptr.h>
 #include <LibJS/Forward.h>
 #include <LibJS/Runtime/Value.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/PixelUnits.h>
 #include <LibWeb/WebDriver/Error.h>
@@ -22,40 +23,40 @@ GC::Ptr<Web::DOM::Node> get_node(HTML::BrowsingContext const&, StringView refere
 String get_or_create_a_node_reference(HTML::BrowsingContext const&, Web::DOM::Node const&);
 bool node_reference_is_known(HTML::BrowsingContext const&, StringView reference);
 
-String get_or_create_a_web_element_reference(HTML::BrowsingContext const&, Web::DOM::Node const& element);
-JsonObject web_element_reference_object(HTML::BrowsingContext const&, Web::DOM::Node const& element);
-bool represents_a_web_element(JsonValue const&);
-bool represents_a_web_element(JS::Value);
+WEB_API String get_or_create_a_web_element_reference(HTML::BrowsingContext const&, Web::DOM::Node const& element);
+WEB_API JsonObject web_element_reference_object(HTML::BrowsingContext const&, Web::DOM::Node const& element);
+WEB_API bool represents_a_web_element(JsonValue const&);
+WEB_API bool represents_a_web_element(JS::Value);
 ErrorOr<GC::Ref<Web::DOM::Element>, WebDriver::Error> deserialize_web_element(Web::HTML::BrowsingContext const&, JsonObject const&);
 ErrorOr<GC::Ref<Web::DOM::Element>, WebDriver::Error> deserialize_web_element(Web::HTML::BrowsingContext const&, JS::Object const&);
-String extract_web_element_reference(JsonObject const&);
-ErrorOr<GC::Ref<Web::DOM::Element>, Web::WebDriver::Error> get_web_element_origin(Web::HTML::BrowsingContext const&, StringView origin);
-ErrorOr<GC::Ref<Web::DOM::Element>, Web::WebDriver::Error> get_known_element(Web::HTML::BrowsingContext const&, StringView reference);
+WEB_API String extract_web_element_reference(JsonObject const&);
+WEB_API ErrorOr<GC::Ref<Web::DOM::Element>, Web::WebDriver::Error> get_web_element_origin(Web::HTML::BrowsingContext const&, StringView origin);
+WEB_API ErrorOr<GC::Ref<Web::DOM::Element>, Web::WebDriver::Error> get_known_element(Web::HTML::BrowsingContext const&, StringView reference);
 
 bool is_element_stale(Web::DOM::Node const& element);
-bool is_element_interactable(Web::HTML::BrowsingContext const&, Web::DOM::Element const&);
+WEB_API bool is_element_interactable(Web::HTML::BrowsingContext const&, Web::DOM::Element const&);
 bool is_element_pointer_interactable(Web::HTML::BrowsingContext const&, Web::DOM::Element const&);
-bool is_element_keyboard_interactable(Web::DOM::Element const&);
+WEB_API bool is_element_keyboard_interactable(Web::DOM::Element const&);
 
-bool is_element_editable(Web::DOM::Element const&);
-bool is_element_mutable(Web::DOM::Element const&);
-bool is_element_mutable_form_control(Web::DOM::Element const&);
-bool is_element_non_typeable_form_control(Web::DOM::Element const&);
+WEB_API bool is_element_editable(Web::DOM::Element const&);
+WEB_API bool is_element_mutable(Web::DOM::Element const&);
+WEB_API bool is_element_mutable_form_control(Web::DOM::Element const&);
+WEB_API bool is_element_non_typeable_form_control(Web::DOM::Element const&);
 
-bool is_element_in_view(ReadonlySpan<GC::Ref<Web::DOM::Element>> paint_tree, Web::DOM::Element&);
-bool is_element_obscured(ReadonlySpan<GC::Ref<Web::DOM::Element>> paint_tree, Web::DOM::Element&);
-GC::RootVector<GC::Ref<Web::DOM::Element>> pointer_interactable_tree(Web::HTML::BrowsingContext&, Web::DOM::Element&);
+WEB_API bool is_element_in_view(ReadonlySpan<GC::Ref<Web::DOM::Element>> paint_tree, Web::DOM::Element&);
+WEB_API bool is_element_obscured(ReadonlySpan<GC::Ref<Web::DOM::Element>> paint_tree, Web::DOM::Element&);
+WEB_API GC::RootVector<GC::Ref<Web::DOM::Element>> pointer_interactable_tree(Web::HTML::BrowsingContext&, Web::DOM::Element&);
 
 String get_or_create_a_shadow_root_reference(HTML::BrowsingContext const&, Web::DOM::ShadowRoot const&);
-JsonObject shadow_root_reference_object(HTML::BrowsingContext const&, Web::DOM::ShadowRoot const&);
+WEB_API JsonObject shadow_root_reference_object(HTML::BrowsingContext const&, Web::DOM::ShadowRoot const&);
 bool represents_a_shadow_root(JsonValue const&);
 bool represents_a_shadow_root(JS::Value);
 ErrorOr<GC::Ref<Web::DOM::ShadowRoot>, WebDriver::Error> deserialize_shadow_root(Web::HTML::BrowsingContext const&, JsonObject const&);
 ErrorOr<GC::Ref<Web::DOM::ShadowRoot>, WebDriver::Error> deserialize_shadow_root(Web::HTML::BrowsingContext const&, JS::Object const&);
-ErrorOr<GC::Ref<Web::DOM::ShadowRoot>, Web::WebDriver::Error> get_known_shadow_root(HTML::BrowsingContext const&, StringView reference);
+WEB_API ErrorOr<GC::Ref<Web::DOM::ShadowRoot>, Web::WebDriver::Error> get_known_shadow_root(HTML::BrowsingContext const&, StringView reference);
 bool is_shadow_root_detached(Web::DOM::ShadowRoot const&);
 
-String element_rendered_text(DOM::Node&);
+WEB_API String element_rendered_text(DOM::Node&);
 
 CSSPixelPoint in_view_center_point(DOM::Element const& element, CSSPixelRect viewport);
 
diff --git a/Libraries/LibWeb/WebDriver/Error.h b/Libraries/LibWeb/WebDriver/Error.h
index ed8c3720008..44782440a33 100644
--- a/Libraries/LibWeb/WebDriver/Error.h
+++ b/Libraries/LibWeb/WebDriver/Error.h
@@ -9,6 +9,7 @@
 
 #include <AK/JsonValue.h>
 #include <AK/String.h>
+#include <LibWeb/Export.h>
 
 namespace Web::WebDriver {
 
@@ -48,7 +49,7 @@ enum class ErrorCode {
 };
 
 // https://w3c.github.io/webdriver/#errors
-struct Error {
+struct WEB_API Error {
     unsigned http_status;
     String error;
     String message;
diff --git a/Libraries/LibWeb/WebDriver/ExecuteScript.h b/Libraries/LibWeb/WebDriver/ExecuteScript.h
index 94c60ba1445..edb78b76df9 100644
--- a/Libraries/LibWeb/WebDriver/ExecuteScript.h
+++ b/Libraries/LibWeb/WebDriver/ExecuteScript.h
@@ -13,6 +13,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Runtime/Promise.h>
 #include <LibJS/Runtime/Value.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::WebDriver {
@@ -24,7 +25,7 @@ struct ExecutionResult {
 
 using OnScriptComplete = GC::Function<void(ExecutionResult)>;
 
-void execute_script(HTML::BrowsingContext const&, String body, GC::RootVector<JS::Value> arguments, Optional<u64> const& timeout_ms, GC::Ref<OnScriptComplete> on_complete);
-void execute_async_script(HTML::BrowsingContext const&, String body, GC::RootVector<JS::Value> arguments, Optional<u64> const& timeout_ms, GC::Ref<OnScriptComplete> on_complete);
+WEB_API void execute_script(HTML::BrowsingContext const&, String body, GC::RootVector<JS::Value> arguments, Optional<u64> const& timeout_ms, GC::Ref<OnScriptComplete> on_complete);
+WEB_API void execute_async_script(HTML::BrowsingContext const&, String body, GC::RootVector<JS::Value> arguments, Optional<u64> const& timeout_ms, GC::Ref<OnScriptComplete> on_complete);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/HeapTimer.h b/Libraries/LibWeb/WebDriver/HeapTimer.h
index 30838b41901..711be4cbb37 100644
--- a/Libraries/LibWeb/WebDriver/HeapTimer.h
+++ b/Libraries/LibWeb/WebDriver/HeapTimer.h
@@ -10,10 +10,11 @@
 #include <LibGC/Function.h>
 #include <LibGC/Ptr.h>
 #include <LibJS/Heap/Cell.h>
+#include <LibWeb/Export.h>
 
 namespace Web::WebDriver {
 
-class HeapTimer : public JS::Cell {
+class WEB_API HeapTimer : public JS::Cell {
     GC_CELL(HeapTimer, JS::Cell);
     GC_DECLARE_ALLOCATOR(HeapTimer);
 
diff --git a/Libraries/LibWeb/WebDriver/InputSource.h b/Libraries/LibWeb/WebDriver/InputSource.h
index 97a7df8d94e..699ececd24e 100644
--- a/Libraries/LibWeb/WebDriver/InputSource.h
+++ b/Libraries/LibWeb/WebDriver/InputSource.h
@@ -11,6 +11,7 @@
 #include <AK/String.h>
 #include <AK/Variant.h>
 #include <AK/Vector.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/PixelUnits.h>
 #include <LibWeb/UIEvents/KeyCode.h>
@@ -76,9 +77,9 @@ struct GlobalKeyState {
 Optional<InputSourceType> input_source_type_from_string(StringView);
 Optional<PointerInputSource::Subtype> pointer_input_source_subtype_from_string(StringView);
 
-InputSource create_input_source(InputState const&, InputSourceType, Optional<PointerInputSource::Subtype>);
-void add_input_source(InputState&, String id, InputSource);
-void remove_input_source(InputState&, StringView id);
+WEB_API InputSource create_input_source(InputState const&, InputSourceType, Optional<PointerInputSource::Subtype>);
+WEB_API void add_input_source(InputState&, String id, InputSource);
+WEB_API void remove_input_source(InputState&, StringView id);
 Optional<InputSource&> get_input_source(InputState&, StringView id);
 ErrorOr<InputSource*, WebDriver::Error> get_or_create_input_source(InputState&, InputSourceType, StringView id, Optional<PointerInputSource::Subtype>);
 
diff --git a/Libraries/LibWeb/WebDriver/InputState.h b/Libraries/LibWeb/WebDriver/InputState.h
index 1e5d1f1e980..a40834bd838 100644
--- a/Libraries/LibWeb/WebDriver/InputState.h
+++ b/Libraries/LibWeb/WebDriver/InputState.h
@@ -9,6 +9,7 @@
 #include <AK/HashMap.h>
 #include <AK/String.h>
 #include <AK/Vector.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebDriver/InputSource.h>
 
@@ -29,7 +30,7 @@ struct InputState {
     Vector<String> actions_queue;
 };
 
-InputState& get_input_state(HTML::BrowsingContext&);
-void reset_input_state(HTML::BrowsingContext&);
+WEB_API InputState& get_input_state(HTML::BrowsingContext&);
+WEB_API void reset_input_state(HTML::BrowsingContext&);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/JSON.h b/Libraries/LibWeb/WebDriver/JSON.h
index 5cf354c2611..70c5c856526 100644
--- a/Libraries/LibWeb/WebDriver/JSON.h
+++ b/Libraries/LibWeb/WebDriver/JSON.h
@@ -8,12 +8,13 @@
 #pragma once
 
 #include <LibJS/Runtime/Value.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebDriver/Response.h>
 
 namespace Web::WebDriver {
 
-Response json_clone(HTML::BrowsingContext const&, JS::Value);
-ErrorOr<JS::Value, WebDriver::Error> json_deserialize(HTML::BrowsingContext const&, JsonValue const&);
+WEB_API Response json_clone(HTML::BrowsingContext const&, JS::Value);
+WEB_API ErrorOr<JS::Value, WebDriver::Error> json_deserialize(HTML::BrowsingContext const&, JsonValue const&);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/Proxy.h b/Libraries/LibWeb/WebDriver/Proxy.h
index dc2e53171b9..114c0492861 100644
--- a/Libraries/LibWeb/WebDriver/Proxy.h
+++ b/Libraries/LibWeb/WebDriver/Proxy.h
@@ -7,13 +7,14 @@
 #pragma once
 
 #include <AK/JsonObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebDriver/Error.h>
 
 namespace Web::WebDriver {
 
 bool has_proxy_configuration();
 void set_has_proxy_configuration(bool);
-void reset_has_proxy_configuration();
+WEB_API void reset_has_proxy_configuration();
 
 ErrorOr<JsonObject, Error> deserialize_as_a_proxy(JsonValue const&);
 
diff --git a/Libraries/LibWeb/WebDriver/Response.h b/Libraries/LibWeb/WebDriver/Response.h
index 17d6f780e7c..3703c4272ca 100644
--- a/Libraries/LibWeb/WebDriver/Response.h
+++ b/Libraries/LibWeb/WebDriver/Response.h
@@ -9,13 +9,14 @@
 #include <AK/JsonValue.h>
 #include <AK/Variant.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebDriver/Error.h>
 
 namespace Web::WebDriver {
 
 // FIXME: Ideally, this could be `using Response = ErrorOr<JsonValue, Error>`, but that won't be
 //        default-constructible, which is a requirement for the generated IPC.
-struct [[nodiscard]] Response {
+struct [[nodiscard]] WEB_API Response {
     Response() = default;
     Response(JsonValue&&);
     Response(Error&&);
@@ -47,9 +48,9 @@ private:
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::WebDriver::Response const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::WebDriver::Response const&);
 
 template<>
-ErrorOr<Web::WebDriver::Response> decode(Decoder&);
+WEB_API ErrorOr<Web::WebDriver::Response> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/Screenshot.h b/Libraries/LibWeb/WebDriver/Screenshot.h
index 7c164ffa296..bcd3b81b793 100644
--- a/Libraries/LibWeb/WebDriver/Screenshot.h
+++ b/Libraries/LibWeb/WebDriver/Screenshot.h
@@ -8,12 +8,13 @@
 
 #include <LibGC/Ptr.h>
 #include <LibGfx/Rect.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebDriver/Response.h>
 
 namespace Web::WebDriver {
 
-ErrorOr<GC::Ref<HTML::HTMLCanvasElement>, WebDriver::Error> draw_bounding_box_from_the_framebuffer(HTML::BrowsingContext&, DOM::Element&, Gfx::IntRect);
-Response encode_canvas_element(HTML::HTMLCanvasElement&);
+WEB_API ErrorOr<GC::Ref<HTML::HTMLCanvasElement>, WebDriver::Error> draw_bounding_box_from_the_framebuffer(HTML::BrowsingContext&, DOM::Element&, Gfx::IntRect);
+WEB_API Response encode_canvas_element(HTML::HTMLCanvasElement&);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/TimeoutsConfiguration.h b/Libraries/LibWeb/WebDriver/TimeoutsConfiguration.h
index 178d82fab23..a3df455fada 100644
--- a/Libraries/LibWeb/WebDriver/TimeoutsConfiguration.h
+++ b/Libraries/LibWeb/WebDriver/TimeoutsConfiguration.h
@@ -8,6 +8,7 @@
 
 #include <AK/Forward.h>
 #include <AK/Optional.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebDriver/Error.h>
 
 namespace Web::WebDriver {
@@ -19,8 +20,8 @@ struct TimeoutsConfiguration {
     Optional<u64> implicit_wait_timeout { 0 };
 };
 
-JsonObject timeouts_object(TimeoutsConfiguration const&);
+WEB_API JsonObject timeouts_object(TimeoutsConfiguration const&);
 ErrorOr<TimeoutsConfiguration, Error> json_deserialize_as_a_timeouts_configuration(JsonValue const&);
-ErrorOr<void, Error> json_deserialize_as_a_timeouts_configuration_into(JsonValue const&, TimeoutsConfiguration&);
+WEB_API ErrorOr<void, Error> json_deserialize_as_a_timeouts_configuration_into(JsonValue const&, TimeoutsConfiguration&);
 
 }
diff --git a/Libraries/LibWeb/WebDriver/UserPrompt.h b/Libraries/LibWeb/WebDriver/UserPrompt.h
index 89fcc18d371..3b17ee376e2 100644
--- a/Libraries/LibWeb/WebDriver/UserPrompt.h
+++ b/Libraries/LibWeb/WebDriver/UserPrompt.h
@@ -11,6 +11,7 @@
 #include <AK/Optional.h>
 #include <AK/StringView.h>
 #include <LibIPC/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebDriver/Response.h>
 
 namespace Web::WebDriver {
@@ -52,22 +53,22 @@ struct PromptHandlerConfiguration {
 // https://w3c.github.io/webdriver/#dfn-user-prompt-handler
 using UserPromptHandler = Optional<HashMap<PromptType, PromptHandlerConfiguration>>;
 
-UserPromptHandler const& user_prompt_handler();
-void set_user_prompt_handler(UserPromptHandler);
+WEB_API UserPromptHandler const& user_prompt_handler();
+WEB_API void set_user_prompt_handler(UserPromptHandler);
 
 Response deserialize_as_an_unhandled_prompt_behavior(JsonValue);
 bool check_user_prompt_handler_matches(JsonObject const&);
-void update_the_user_prompt_handler(JsonObject const&);
-JsonValue serialize_the_user_prompt_handler();
+WEB_API void update_the_user_prompt_handler(JsonObject const&);
+WEB_API JsonValue serialize_the_user_prompt_handler();
 
 }
 
 namespace IPC {
 
 template<>
-ErrorOr<void> encode(Encoder&, Web::WebDriver::PromptHandlerConfiguration const&);
+WEB_API ErrorOr<void> encode(Encoder&, Web::WebDriver::PromptHandlerConfiguration const&);
 
 template<>
-ErrorOr<Web::WebDriver::PromptHandlerConfiguration> decode(Decoder&);
+WEB_API ErrorOr<Web::WebDriver::PromptHandlerConfiguration> decode(Decoder&);
 
 }
diff --git a/Libraries/LibWeb/WebGL/OpenGLContext.h b/Libraries/LibWeb/WebGL/OpenGLContext.h
index 7a7ac5a4d5e..67fddf53113 100644
--- a/Libraries/LibWeb/WebGL/OpenGLContext.h
+++ b/Libraries/LibWeb/WebGL/OpenGLContext.h
@@ -8,10 +8,11 @@
 
 #include <LibGfx/Forward.h>
 #include <LibGfx/Size.h>
+#include <LibWeb/Export.h>
 
 namespace Web::WebGL {
 
-class OpenGLContext {
+class WEB_API OpenGLContext {
 public:
     enum class WebGLVersion {
         WebGL1,
diff --git a/Libraries/LibWeb/WebGL/WebGLObject.h b/Libraries/LibWeb/WebGL/WebGLObject.h
index 9ae822d313a..8580ec8a175 100644
--- a/Libraries/LibWeb/WebGL/WebGLObject.h
+++ b/Libraries/LibWeb/WebGL/WebGLObject.h
@@ -9,12 +9,13 @@
 #pragma once
 
 #include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebGL/Types.h>
 #include <LibWeb/WebGL/WebGLRenderingContextBase.h>
 
 namespace Web::WebGL {
 
-class WebGLObject : public Bindings::PlatformObject {
+class WEB_API WebGLObject : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(WebGLObject, Bindings::PlatformObject);
 
 public:
diff --git a/Libraries/LibWeb/WebIDL/AbstractOperations.cpp b/Libraries/LibWeb/WebIDL/AbstractOperations.cpp
index cad409def2e..5d43f3f2409 100644
--- a/Libraries/LibWeb/WebIDL/AbstractOperations.cpp
+++ b/Libraries/LibWeb/WebIDL/AbstractOperations.cpp
@@ -15,6 +15,7 @@
 #include <LibJS/Runtime/FunctionObject.h>
 #include <LibJS/Runtime/TypedArray.h>
 #include <LibJS/Runtime/ValueInlines.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/Scripting/Environments.h>
 #include <LibWeb/HTML/WindowOrWorkerGlobalScope.h>
 #include <LibWeb/WebIDL/AbstractOperations.h>
@@ -538,14 +539,14 @@ JS::ThrowCompletionOr<T> convert_to_int(JS::VM& vm, JS::Value value, EnforceRang
     return x;
 }
 
-template JS::ThrowCompletionOr<Byte> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
-template JS::ThrowCompletionOr<Octet> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
-template JS::ThrowCompletionOr<Short> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
-template JS::ThrowCompletionOr<UnsignedShort> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
-template JS::ThrowCompletionOr<Long> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
-template JS::ThrowCompletionOr<UnsignedLong> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
-template JS::ThrowCompletionOr<LongLong> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
-template JS::ThrowCompletionOr<UnsignedLongLong> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<Byte> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<Octet> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<Short> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<UnsignedShort> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<Long> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<UnsignedLong> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<LongLong> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
+template WEB_API JS::ThrowCompletionOr<UnsignedLongLong> convert_to_int(JS::VM& vm, JS::Value, EnforceRange, Clamp);
 
 // AD-HOC: For same-object caching purposes, this can be used to compare a cached JS array of DOM::Elements with another
 //         list. Either list can be null, in which case they are considered the same only if they are both null.
diff --git a/Libraries/LibWeb/WebIDL/AbstractOperations.h b/Libraries/LibWeb/WebIDL/AbstractOperations.h
index c1860ca5153..811f4e5146c 100644
--- a/Libraries/LibWeb/WebIDL/AbstractOperations.h
+++ b/Libraries/LibWeb/WebIDL/AbstractOperations.h
@@ -12,19 +12,20 @@
 #include <LibGC/Ptr.h>
 #include <LibGC/RootVector.h>
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::WebIDL {
 
 bool is_buffer_source_type(JS::Value);
 GC::Ptr<JS::ArrayBuffer> underlying_buffer_source(JS::Object& buffer_source);
-ErrorOr<ByteBuffer> get_buffer_source_copy(JS::Object const& buffer_source);
+WEB_API ErrorOr<ByteBuffer> get_buffer_source_copy(JS::Object const& buffer_source);
 
 JS::Completion call_user_object_operation(CallbackType& callback, Utf16FlyString const& operation_name, Optional<JS::Value> this_argument, ReadonlySpan<JS::Value> args);
 
-JS::ThrowCompletionOr<String> to_string(JS::VM&, JS::Value);
-JS::ThrowCompletionOr<Utf16String> to_utf16_string(JS::VM&, JS::Value);
-JS::ThrowCompletionOr<String> to_usv_string(JS::VM&, JS::Value);
+WEB_API JS::ThrowCompletionOr<String> to_string(JS::VM&, JS::Value);
+WEB_API JS::ThrowCompletionOr<Utf16String> to_utf16_string(JS::VM&, JS::Value);
+WEB_API JS::ThrowCompletionOr<String> to_usv_string(JS::VM&, JS::Value);
 JS::ThrowCompletionOr<Utf16String> to_utf16_usv_string(JS::VM&, JS::Value);
 JS::ThrowCompletionOr<String> to_byte_string(JS::VM&, JS::Value);
 
@@ -33,10 +34,10 @@ enum class ExceptionBehavior {
     Report,
     Rethrow,
 };
-JS::Completion invoke_callback(CallbackType& callback, Optional<JS::Value> this_argument, ExceptionBehavior exception_behavior, ReadonlySpan<JS::Value> args);
-JS::Completion invoke_callback(CallbackType& callback, Optional<JS::Value> this_argument, ReadonlySpan<JS::Value> args);
+WEB_API JS::Completion invoke_callback(CallbackType& callback, Optional<JS::Value> this_argument, ExceptionBehavior exception_behavior, ReadonlySpan<JS::Value> args);
+WEB_API JS::Completion invoke_callback(CallbackType& callback, Optional<JS::Value> this_argument, ReadonlySpan<JS::Value> args);
 
-GC::Ref<Promise> invoke_promise_callback(CallbackType& callback, Optional<JS::Value> this_argument, ReadonlySpan<JS::Value> args);
+WEB_API GC::Ref<Promise> invoke_promise_callback(CallbackType& callback, Optional<JS::Value> this_argument, ReadonlySpan<JS::Value> args);
 
 JS::Completion construct(CallbackType& callable, ReadonlySpan<JS::Value> args);
 
diff --git a/Libraries/LibWeb/WebIDL/AsyncIterator.h b/Libraries/LibWeb/WebIDL/AsyncIterator.h
index ff966bdf0c1..d7bf4ce44fb 100644
--- a/Libraries/LibWeb/WebIDL/AsyncIterator.h
+++ b/Libraries/LibWeb/WebIDL/AsyncIterator.h
@@ -11,11 +11,12 @@
 #include <LibJS/Runtime/PromiseCapability.h>
 #include <LibJS/Runtime/Realm.h>
 #include <LibJS/Runtime/VM.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/Promise.h>
 
 namespace Web::WebIDL {
 
-class AsyncIterator : public Bindings::PlatformObject {
+class WEB_API AsyncIterator : public Bindings::PlatformObject {
     WEB_PLATFORM_OBJECT(AsyncIterator, Bindings::PlatformObject);
     GC_DECLARE_ALLOCATOR(AsyncIterator);
 
diff --git a/Libraries/LibWeb/WebIDL/DOMException.h b/Libraries/LibWeb/WebIDL/DOMException.h
index bb022db1626..cd6a74ec9e9 100644
--- a/Libraries/LibWeb/WebIDL/DOMException.h
+++ b/Libraries/LibWeb/WebIDL/DOMException.h
@@ -10,6 +10,7 @@
 #include <AK/Utf16String.h>
 #include <LibWeb/Bindings/PlatformObject.h>
 #include <LibWeb/Bindings/Serializable.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/HTML/Scripting/Environments.h>
 
@@ -91,7 +92,7 @@ static u16 get_legacy_code_for_name(FlyString const& name)
 }
 
 // https://webidl.spec.whatwg.org/#idl-DOMException
-class DOMException final
+class WEB_API DOMException final
     : public Bindings::PlatformObject
     , public Bindings::Serializable {
     WEB_PLATFORM_OBJECT(DOMException, Bindings::PlatformObject);
diff --git a/Libraries/LibWeb/WebIDL/ObservableArray.h b/Libraries/LibWeb/WebIDL/ObservableArray.h
index 6cea86495e3..224937addf2 100644
--- a/Libraries/LibWeb/WebIDL/ObservableArray.h
+++ b/Libraries/LibWeb/WebIDL/ObservableArray.h
@@ -7,12 +7,13 @@
 #pragma once
 
 #include <LibJS/Runtime/Array.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::WebIDL {
 
 // https://webidl.spec.whatwg.org/#idl-observable-array
-class ObservableArray final : public JS::Array {
+class WEB_API ObservableArray final : public JS::Array {
     JS_OBJECT(ObservableArray, JS::Array);
     GC_DECLARE_ALLOCATOR(ObservableArray);
 
diff --git a/Libraries/LibWeb/WebIDL/OverloadResolution.h b/Libraries/LibWeb/WebIDL/OverloadResolution.h
index 14cf87383de..50a7d843e6e 100644
--- a/Libraries/LibWeb/WebIDL/OverloadResolution.h
+++ b/Libraries/LibWeb/WebIDL/OverloadResolution.h
@@ -11,6 +11,7 @@
 #include <AK/Vector.h>
 #include <LibIDL/Types.h>
 #include <LibJS/Runtime/VM.h>
+#include <LibWeb/Export.h>
 
 namespace Web::WebIDL {
 
@@ -24,6 +25,6 @@ struct ResolvedOverload {
 };
 
 // https://webidl.spec.whatwg.org/#es-overloads
-JS::ThrowCompletionOr<ResolvedOverload> resolve_overload(JS::VM&, IDL::EffectiveOverloadSet&, ReadonlySpan<StringView> interface_dictionaries);
+WEB_API JS::ThrowCompletionOr<ResolvedOverload> resolve_overload(JS::VM&, IDL::EffectiveOverloadSet&, ReadonlySpan<StringView> interface_dictionaries);
 
 }
diff --git a/Libraries/LibWeb/WebIDL/Promise.h b/Libraries/LibWeb/WebIDL/Promise.h
index 6fdfbb49799..c85f1fddd64 100644
--- a/Libraries/LibWeb/WebIDL/Promise.h
+++ b/Libraries/LibWeb/WebIDL/Promise.h
@@ -10,6 +10,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Runtime/PromiseCapability.h>
 #include <LibJS/Runtime/Value.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 #include <LibWeb/WebIDL/ExceptionOr.h>
 
@@ -20,20 +21,20 @@ using ReactionSteps = GC::Function<WebIDL::ExceptionOr<JS::Value>(JS::Value)>;
 // https://webidl.spec.whatwg.org/#es-promise
 using Promise = JS::PromiseCapability;
 
-GC::Ref<Promise> create_promise(JS::Realm&);
-GC::Ref<Promise> create_resolved_promise(JS::Realm&, JS::Value);
-GC::Ref<Promise> create_rejected_promise(JS::Realm&, JS::Value);
-void resolve_promise(JS::Realm&, Promise const&, JS::Value = JS::js_undefined());
-void reject_promise(JS::Realm&, Promise const&, JS::Value);
-GC::Ref<Promise> react_to_promise(Promise const&, GC::Ptr<ReactionSteps> on_fulfilled_callback, GC::Ptr<ReactionSteps> on_rejected_callback);
-GC::Ref<Promise> upon_fulfillment(Promise const&, GC::Ref<ReactionSteps>);
-GC::Ref<Promise> upon_rejection(Promise const&, GC::Ref<ReactionSteps>);
-void mark_promise_as_handled(Promise const&);
-bool is_promise_fulfilled(Promise const&);
-void wait_for_all(JS::Realm&, Vector<GC::Ref<Promise>> const& promises, Function<void(Vector<JS::Value> const&)> success_steps, Function<void(JS::Value)> failure_steps);
-GC::Ref<Promise> get_promise_for_wait_for_all(JS::Realm&, Vector<GC::Ref<Promise>> const& promises);
+WEB_API GC::Ref<Promise> create_promise(JS::Realm&);
+WEB_API GC::Ref<Promise> create_resolved_promise(JS::Realm&, JS::Value);
+WEB_API GC::Ref<Promise> create_rejected_promise(JS::Realm&, JS::Value);
+WEB_API void resolve_promise(JS::Realm&, Promise const&, JS::Value = JS::js_undefined());
+WEB_API void reject_promise(JS::Realm&, Promise const&, JS::Value);
+WEB_API GC::Ref<Promise> react_to_promise(Promise const&, GC::Ptr<ReactionSteps> on_fulfilled_callback, GC::Ptr<ReactionSteps> on_rejected_callback);
+WEB_API GC::Ref<Promise> upon_fulfillment(Promise const&, GC::Ref<ReactionSteps>);
+WEB_API GC::Ref<Promise> upon_rejection(Promise const&, GC::Ref<ReactionSteps>);
+WEB_API void mark_promise_as_handled(Promise const&);
+WEB_API bool is_promise_fulfilled(Promise const&);
+WEB_API void wait_for_all(JS::Realm&, Vector<GC::Ref<Promise>> const& promises, Function<void(Vector<JS::Value> const&)> success_steps, Function<void(JS::Value)> failure_steps);
+WEB_API GC::Ref<Promise> get_promise_for_wait_for_all(JS::Realm&, Vector<GC::Ref<Promise>> const& promises);
 
 // Non-spec, convenience method.
-GC::Ref<Promise> create_rejected_promise_from_exception(JS::Realm&, Exception);
+WEB_API GC::Ref<Promise> create_rejected_promise_from_exception(JS::Realm&, Exception);
 
 }
diff --git a/Libraries/LibWeb/WebIDL/Tracing.h b/Libraries/LibWeb/WebIDL/Tracing.h
index 9b4ed8f7e05..45d151a3890 100644
--- a/Libraries/LibWeb/WebIDL/Tracing.h
+++ b/Libraries/LibWeb/WebIDL/Tracing.h
@@ -7,11 +7,12 @@
 #pragma once
 
 #include <LibJS/Forward.h>
+#include <LibWeb/Export.h>
 
 namespace Web::WebIDL {
 
 void log_trace(JS::VM& vm, char const* function);
 
-void set_enable_idl_tracing(bool enabled);
+WEB_API void set_enable_idl_tracing(bool enabled);
 
 }
diff --git a/Libraries/LibWeb/Worker/WebWorkerClient.h b/Libraries/LibWeb/Worker/WebWorkerClient.h
index c2b616ae812..ecaffd5d1f2 100644
--- a/Libraries/LibWeb/Worker/WebWorkerClient.h
+++ b/Libraries/LibWeb/Worker/WebWorkerClient.h
@@ -7,12 +7,13 @@
 #pragma once
 
 #include <LibIPC/ConnectionToServer.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Worker/WebWorkerClientEndpoint.h>
 #include <LibWeb/Worker/WebWorkerServerEndpoint.h>
 
 namespace Web::HTML {
 
-class WebWorkerClient final
+class WEB_API WebWorkerClient final
     : public IPC::ConnectionToServer<WebWorkerClientEndpoint, WebWorkerServerEndpoint>
     , public WebWorkerClientEndpoint {
     C_OBJECT_ABSTRACT(WebWorkerClient);
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSKeyword.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSKeyword.cpp
index b4c342e903f..0b52357caf5 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSKeyword.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSKeyword.cpp
@@ -56,6 +56,7 @@ ErrorOr<void> generate_header_file(JsonArray& keyword_data, Core::File& file)
 
 #include <AK/StringView.h>
 #include <AK/Traits.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
@@ -75,7 +76,7 @@ enum class Keyword : @keyword_underlying_type@ {
     generator.append(R"~~~(
 };
 
-Optional<Keyword> keyword_from_string(StringView);
+WEB_API Optional<Keyword> keyword_from_string(StringView);
 StringView string_from_keyword(Keyword);
 
 // https://www.w3.org/TR/css-values-4/#common-keywords
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPropertyID.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPropertyID.cpp
index c22bc3f7ad1..405c39e7c81 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPropertyID.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPropertyID.cpp
@@ -166,6 +166,7 @@ ErrorOr<void> generate_header_file(JsonObject& properties, JsonObject& logical_p
 #include <LibJS/Forward.h>
 #include <LibWeb/CSS/Enums.h>
 #include <LibWeb/CSS/ValueType.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/Forward.h>
 
 namespace Web::CSS {
@@ -250,10 +251,10 @@ AnimationType animation_type_from_longhand_property(PropertyID);
 bool is_animatable_property(PropertyID);
 
 Optional<PropertyID> property_id_from_camel_case_string(StringView);
-Optional<PropertyID> property_id_from_string(StringView);
-[[nodiscard]] FlyString const& string_from_property_id(PropertyID);
+WEB_API Optional<PropertyID> property_id_from_string(StringView);
+[[nodiscard]] WEB_API FlyString const& string_from_property_id(PropertyID);
 [[nodiscard]] FlyString const& camel_case_string_from_property_id(PropertyID);
-bool is_inherited_property(PropertyID);
+WEB_API bool is_inherited_property(PropertyID);
 NonnullRefPtr<StyleValue const> property_initial_value(PropertyID);
 
 bool property_accepts_type(PropertyID, ValueType);
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp
index 6455b00b0b6..0ed39b62b9f 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateCSSPseudoElement.cpp
@@ -59,6 +59,7 @@ ErrorOr<void> generate_header_file(JsonObject& pseudo_elements_data, Core::File&
 #include <AK/Optional.h>
 #include <AK/StringView.h>
 #include <LibWeb/CSS/PropertyID.h>
+#include <LibWeb/Export.h>
 
 namespace Web::CSS {
 
@@ -83,7 +84,7 @@ enum class PseudoElement : @pseudo_element_underlying_type@ {
 
 Optional<PseudoElement> pseudo_element_from_string(StringView);
 Optional<PseudoElement> aliased_pseudo_element_from_string(StringView);
-StringView pseudo_element_name(PseudoElement);
+WEB_API StringView pseudo_element_name(PseudoElement);
 
 bool is_has_allowed_pseudo_element(PseudoElement);
 bool is_pseudo_element_root(PseudoElement);
diff --git a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWindowOrWorkerInterfaces.cpp b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWindowOrWorkerInterfaces.cpp
index 4cca490f365..ee138c338d4 100644
--- a/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWindowOrWorkerInterfaces.cpp
+++ b/Meta/Lagom/Tools/CodeGenerators/LibWeb/GenerateWindowOrWorkerInterfaces.cpp
@@ -77,6 +77,7 @@ static ErrorOr<void> generate_intrinsic_definitions(StringView output_path, Inte
 #include <LibGC/DeferGC.h>
 #include <LibJS/Runtime/Object.h>
 #include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Export.h>
 #include <LibWeb/HTML/Window.h>
 #include <LibWeb/HTML/DedicatedWorkerGlobalScope.h>
 #include <LibWeb/HTML/SharedWorkerGlobalScope.h>
@@ -211,7 +212,7 @@ bool Intrinsics::is_interface_exposed<@prototype_class@>(JS::Realm& realm) const
 
         gen.append(R"~~~(
 template<>
-void Intrinsics::create_web_prototype_and_constructor<@prototype_class@>(JS::Realm& realm)
+WEB_API void Intrinsics::create_web_prototype_and_constructor<@prototype_class@>(JS::Realm& realm)
 {
     auto& vm = realm.vm();
 
diff --git a/Services/WebContent/CMakeLists.txt b/Services/WebContent/CMakeLists.txt
index 213e89caa9b..1da97b3823f 100644
--- a/Services/WebContent/CMakeLists.txt
+++ b/Services/WebContent/CMakeLists.txt
@@ -52,33 +52,6 @@ endif()
 target_link_libraries(WebContent PRIVATE webcontentservice LibURL)
 
 if(WIN32)
-    # FIXME: This is a hack to get around lld-link error undefined symbols in LibWeb
-    target_link_libraries(WebContent PRIVATE
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,AbortSignal>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,AttributeNames>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,Buffers>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,CallbackType>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,DocumentObserver>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,EventNames>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,Fetching>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,HeapTimer>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,MutationType>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,Namespace>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,NavigationObserver>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,PaintableBox>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,Policy>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,PolicyContainer>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,PullIntoDescriptor>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,ReadableByteStreamController>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,ReadableStream>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,ShadowRoot>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,TagNames>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,Text>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,Tracing>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,TransformStream>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,WebUI>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,WritableStream>
-    )
     find_package(unofficial-angle REQUIRED CONFIG)
     target_link_libraries(WebContent PRIVATE LibTextCodec unofficial::angle::libGLESv2)
 endif()
diff --git a/Services/WebContent/main.cpp b/Services/WebContent/main.cpp
index 74c70bc2368..0ad9dc9f823 100644
--- a/Services/WebContent/main.cpp
+++ b/Services/WebContent/main.cpp
@@ -156,7 +156,7 @@ ErrorOr<int> ladybird_main(Main::Arguments arguments)
         Web::Fetch::Fetching::set_http_cache_enabled(true);
     }
 
-    Web::Painting::g_paint_viewport_scrollbars = !disable_scrollbar_painting;
+    Web::Painting::set_paint_viewport_scrollbars(!disable_scrollbar_painting);
 
     if (!echo_server_port_string_view.is_empty()) {
         if (auto maybe_echo_server_port = echo_server_port_string_view.to_number<u16>(); maybe_echo_server_port.has_value())
diff --git a/Services/WebWorker/CMakeLists.txt b/Services/WebWorker/CMakeLists.txt
index 1567cd228ab..d6589415c7f 100644
--- a/Services/WebWorker/CMakeLists.txt
+++ b/Services/WebWorker/CMakeLists.txt
@@ -22,17 +22,6 @@ target_include_directories(WebWorker PRIVATE ${LADYBIRD_SOURCE_DIR})
 target_link_libraries(WebWorker PRIVATE webworkerservice)
 
 if(WIN32)
-    # FIXME: This is a hack to get around lld-link error undefined symbols in LibWeb
-    target_link_libraries(webworkerservice PRIVATE
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,CallbackType>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,DedicatedWorkerGlobalScope>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,EnvironmentSettingsSnapshot>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,EventNames>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,SharedWorkerGlobalScope>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,Tracing>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,WorkerDebugConsoleClient>
-            $<FILTER:$<TARGET_OBJECTS:LibWeb>,INCLUDE,WorkerLocation>
-    )
     find_package(pthread REQUIRED)
     target_include_directories(WebWorker PRIVATE $<BUILD_INTERFACE:${PTHREAD_INCLUDE_DIR}>)
 endif()