diff --git a/baselines/audioworklet.tostringtag.generated.d.ts b/baselines/audioworklet.tostringtag.generated.d.ts
new file mode 100644
index 000000000..25dd2b782
--- /dev/null
+++ b/baselines/audioworklet.tostringtag.generated.d.ts
@@ -0,0 +1,99 @@
+/////////////////////////////
+/// AudioWorklet [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioWorkletProcessor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkletGlobalScope {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/dom.tostringtag.generated.d.ts b/baselines/dom.tostringtag.generated.d.ts
new file mode 100644
index 000000000..387297218
--- /dev/null
+++ b/baselines/dom.tostringtag.generated.d.ts
@@ -0,0 +1,935 @@
+/////////////////////////////
+/// Window [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AbstractRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AnimationEffect {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AnimationTimeline {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioListener {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioParam {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioParamMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AuthenticatorResponse {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface BarProp {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSRule {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSRuleList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleDeclaration {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CaretPosition {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ClipboardItem {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Credential {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CredentialsContainer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CustomElementRegistry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CustomStateSet {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMImplementation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMParser {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMTokenList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DataTransfer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DataTransferItem {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DataTransferItemList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ElementInternals {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EncodedVideoChunk {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventCounts {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface External {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystem {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemDirectoryReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Gamepad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GamepadButton {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GamepadHapticActuator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Geolocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GeolocationCoordinates {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GeolocationPosition {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GeolocationPositionError {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface HTMLAllCollection {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface HTMLCollection {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Highlight {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface HighlightRegistry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface History {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IdleDeadline {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IntersectionObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IntersectionObserverEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Location {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MIDIInputMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MIDIOutputMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaDeviceInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaError {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaKeyStatusMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaKeySystemAccess {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaKeys {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaMetadata {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaSession {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaSourceHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MimeType {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MimeTypeArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MutationObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MutationRecord {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NamedNodeMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Navigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NodeIterator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NodeList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PaymentAddress {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceNavigation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PeriodicWave {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Plugin {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PluginArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCCertificate {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedAudioFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedVideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCIceCandidate {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpReceiver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpScriptTransform {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpSender {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpTransceiver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCSessionDescription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCStatsReport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ResizeObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ResizeObserverEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ResizeObserverSize {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAngle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedAngle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedBoolean {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedEnumeration {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedInteger {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedLength {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedLengthList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedNumber {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedNumberList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedPreserveAspectRatio {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedRect {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedString {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedTransformList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGLength {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGLengthList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGNumber {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGNumberList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGPointList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGPreserveAspectRatio {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGTransform {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGTransformList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGUnitTypes {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Screen {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Selection {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechRecognitionAlternative {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechRecognitionResult {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechRecognitionResultList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechSynthesisVoice {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Storage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StyleSheet {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StyleSheetList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextTrackCueList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TimeRanges {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Touch {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TouchList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TreeWalker {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface UserActivation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VTTRegion {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ValidityState {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoColorSpace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoPlaybackQuality {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ViewTransition {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WakeLock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Worklet {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XMLSerializer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XPathEvaluator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XPathExpression {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XPathResult {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XSLTProcessor {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/serviceworker.tostringtag.generated.d.ts b/baselines/serviceworker.tostringtag.generated.d.ts
new file mode 100644
index 000000000..959c62add
--- /dev/null
+++ b/baselines/serviceworker.tostringtag.generated.d.ts
@@ -0,0 +1,399 @@
+/////////////////////////////
+/// ServiceWorker [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Client {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Clients {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushMessageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerNavigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/sharedworker.tostringtag.generated.d.ts b/baselines/sharedworker.tostringtag.generated.d.ts
new file mode 100644
index 000000000..c2c9cb6e6
--- /dev/null
+++ b/baselines/sharedworker.tostringtag.generated.d.ts
@@ -0,0 +1,391 @@
+/////////////////////////////
+/// SharedWorker [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileReaderSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerNavigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/ts5.5/audioworklet.tostringtag.generated.d.ts b/baselines/ts5.5/audioworklet.tostringtag.generated.d.ts
new file mode 100644
index 000000000..25dd2b782
--- /dev/null
+++ b/baselines/ts5.5/audioworklet.tostringtag.generated.d.ts
@@ -0,0 +1,99 @@
+/////////////////////////////
+/// AudioWorklet [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioWorkletProcessor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkletGlobalScope {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/ts5.5/dom.tostringtag.generated.d.ts b/baselines/ts5.5/dom.tostringtag.generated.d.ts
new file mode 100644
index 000000000..387297218
--- /dev/null
+++ b/baselines/ts5.5/dom.tostringtag.generated.d.ts
@@ -0,0 +1,935 @@
+/////////////////////////////
+/// Window [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AbstractRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AnimationEffect {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AnimationTimeline {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioListener {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioParam {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AudioParamMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface AuthenticatorResponse {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface BarProp {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSRule {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSRuleList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleDeclaration {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CaretPosition {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ClipboardItem {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Credential {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CredentialsContainer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CustomElementRegistry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CustomStateSet {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMImplementation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMParser {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMTokenList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DataTransfer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DataTransferItem {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DataTransferItemList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ElementInternals {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EncodedVideoChunk {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventCounts {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface External {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystem {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemDirectoryReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Gamepad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GamepadButton {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GamepadHapticActuator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Geolocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GeolocationCoordinates {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GeolocationPosition {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface GeolocationPositionError {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface HTMLAllCollection {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface HTMLCollection {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Highlight {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface HighlightRegistry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface History {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IdleDeadline {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IntersectionObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IntersectionObserverEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Location {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MIDIInputMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MIDIOutputMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaDeviceInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaError {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaKeyStatusMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaKeySystemAccess {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaKeys {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaMetadata {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaSession {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaSourceHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MimeType {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MimeTypeArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MutationObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MutationRecord {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NamedNodeMap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Navigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NodeIterator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NodeList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PaymentAddress {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceNavigation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PeriodicWave {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Plugin {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PluginArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCCertificate {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedAudioFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedVideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCIceCandidate {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpReceiver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpScriptTransform {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpSender {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCRtpTransceiver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCSessionDescription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCStatsReport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ResizeObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ResizeObserverEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ResizeObserverSize {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAngle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedAngle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedBoolean {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedEnumeration {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedInteger {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedLength {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedLengthList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedNumber {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedNumberList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedPreserveAspectRatio {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedRect {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedString {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGAnimatedTransformList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGLength {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGLengthList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGNumber {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGNumberList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGPointList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGPreserveAspectRatio {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGTransform {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGTransformList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SVGUnitTypes {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Screen {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Selection {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechRecognitionAlternative {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechRecognitionResult {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechRecognitionResultList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SpeechSynthesisVoice {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Storage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StyleSheet {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StyleSheetList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextTrackCueList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TimeRanges {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Touch {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TouchList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TreeWalker {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface UserActivation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VTTRegion {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ValidityState {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoColorSpace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoPlaybackQuality {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ViewTransition {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WakeLock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Worklet {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XMLSerializer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XPathEvaluator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XPathExpression {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XPathResult {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface XSLTProcessor {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/ts5.5/serviceworker.tostringtag.generated.d.ts b/baselines/ts5.5/serviceworker.tostringtag.generated.d.ts
new file mode 100644
index 000000000..959c62add
--- /dev/null
+++ b/baselines/ts5.5/serviceworker.tostringtag.generated.d.ts
@@ -0,0 +1,399 @@
+/////////////////////////////
+/// ServiceWorker [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Client {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Clients {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushMessageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerNavigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/ts5.5/sharedworker.tostringtag.generated.d.ts b/baselines/ts5.5/sharedworker.tostringtag.generated.d.ts
new file mode 100644
index 000000000..c2c9cb6e6
--- /dev/null
+++ b/baselines/ts5.5/sharedworker.tostringtag.generated.d.ts
@@ -0,0 +1,391 @@
+/////////////////////////////
+/// SharedWorker [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileReaderSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerNavigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/ts5.5/webworker.tostringtag.generated.d.ts b/baselines/ts5.5/webworker.tostringtag.generated.d.ts
new file mode 100644
index 000000000..cbba4be96
--- /dev/null
+++ b/baselines/ts5.5/webworker.tostringtag.generated.d.ts
@@ -0,0 +1,435 @@
+/////////////////////////////
+/// Worker [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Client {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Clients {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EncodedVideoChunk {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileReaderSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemSyncAccessHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaSourceHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaStreamTrackProcessor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushMessageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedAudioFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedVideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoColorSpace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerNavigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/baselines/webworker.tostringtag.generated.d.ts b/baselines/webworker.tostringtag.generated.d.ts
new file mode 100644
index 000000000..cbba4be96
--- /dev/null
+++ b/baselines/webworker.tostringtag.generated.d.ts
@@ -0,0 +1,435 @@
+/////////////////////////////
+/// Worker [Symbol.toStringTag] APIs
+/////////////////////////////
+
+interface AbortController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Blob {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSNumericArray {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSStyleValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSTransformComponent {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CSSVariableReferenceValue {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Cache {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CacheStorage {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasGradient {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CanvasPattern {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Client {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Clients {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Crypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface CryptoKey {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMMatrixReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMPointReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMQuad {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMRectReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DOMStringList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface DecompressionStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EncodedVideoChunk {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Event {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface EventTarget {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileReaderSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FileSystemSyncAccessHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FontFace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface FormData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Headers {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBCursor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBFactory {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBIndex {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBKeyRange {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface IDBObjectStore {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmap {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageBitmapRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ImageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Lock {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface LockManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaCapabilities {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaSourceHandle {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MediaStreamTrackProcessor {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface MessageChannel {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface NavigationPreloadManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface OffscreenCanvasRenderingContext2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Path2D {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceEntry {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceObserverEntryList {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PerformanceServerTiming {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Permissions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushMessageData {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscription {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface PushSubscriptionOptions {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedAudioFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface RTCEncodedVideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableByteStreamController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamBYOBRequest {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReadableStreamDefaultReader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Report {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportBody {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface ReportingObserver {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Request {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface Response {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StorageManager {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface StylePropertyMapReadOnly {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface SubtleCrypto {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextDecoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoder {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextEncoderStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TextMetrics {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface TransformStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URL {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface URLSearchParams {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoColorSpace {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface VideoFrame {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGL2RenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLActiveInfo {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLBuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLFramebuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLProgram {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLQuery {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderbuffer {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLRenderingContext {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSampler {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShader {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLShaderPrecisionFormat {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLSync {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTexture {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLTransformFeedback {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLUniformLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebGLVertexArrayObject {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransport {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportBidirectionalStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WebTransportDatagramDuplexStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerLocation {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WorkerNavigator {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStream {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultController {
+    readonly [Symbol.toStringTag]: string;
+}
+
+interface WritableStreamDefaultWriter {
+    readonly [Symbol.toStringTag]: string;
+}
diff --git a/src/build.ts b/src/build.ts
index 45b35612a..7cb8f35e8 100644
--- a/src/build.ts
+++ b/src/build.ts
@@ -60,10 +60,21 @@ async function emitFlavor(
     result,
   );
 
+  const toStringTag = emitWebIdl(
+    exposed,
+    options.global[0],
+    "toStringTag",
+    options.useIteratorObject,
+  );
+  await fs.writeFile(
+    new URL(`${options.name}.tostringtag.generated.d.ts`, options.outputFolder),
+    toStringTag,
+  );
+
   const iterators = emitWebIdl(
     exposed,
     options.global[0],
-    "sync",
+    "iterator",
     options.useIteratorObject,
   );
   await fs.writeFile(
@@ -74,7 +85,7 @@ async function emitFlavor(
   const asyncIterators = emitWebIdl(
     exposed,
     options.global[0],
-    "async",
+    "asyncIterator",
     options.useIteratorObject,
   );
   await fs.writeFile(
diff --git a/src/build/emitter.ts b/src/build/emitter.ts
index 7ac260ce4..e81bc9855 100644
--- a/src/build/emitter.ts
+++ b/src/build/emitter.ts
@@ -135,7 +135,7 @@ function isEventHandler(p: Browser.Property) {
 export function emitWebIdl(
   webidl: Browser.WebIdl,
   global: string,
-  iterator: "" | "sync" | "async",
+  flavor: "" | "iterator" | "asyncIterator" | "toStringTag",
   useIteratorObject: boolean,
 ): string {
   // Global print target
@@ -231,10 +231,12 @@ export function emitWebIdl(
     getParentsWithConstant,
   );
 
-  switch (iterator) {
-    case "sync":
+  switch (flavor) {
+    case "toStringTag":
+      return emitES6ToStringTag();
+    case "iterator":
       return emitES6DomIterators();
-    case "async":
+    case "asyncIterator":
       return emitES2018DomAsyncIterators();
     default:
       return emit();
@@ -423,7 +425,7 @@ export function emitWebIdl(
   }
 
   function convertDomTypeToTsTypeSimple(objDomType: string): string {
-    if (objDomType === "sequence" && iterator !== "") {
+    if (objDomType === "sequence" && flavor !== "") {
       return "Iterable";
     }
     if (baseTypeConversionMap.has(objDomType)) {
@@ -1802,6 +1804,35 @@ export function emitWebIdl(
     printer.printLine("}");
   }
 
+  function emitES6ToStringTag() {
+    printer.reset();
+    printer.printLine("/////////////////////////////");
+    printer.printLine(`/// ${global} [Symbol.toStringTag] APIs`);
+    printer.printLine("/////////////////////////////");
+
+    const toStringTagProperty = {
+      type: "USVString",
+      name: "[Symbol.toStringTag]",
+      readonly: true,
+    };
+
+    const interfaces = getElements(webidl.interfaces, "interface");
+    interfaces.sort(compareName).forEach((i) => {
+      if (!i.noInterfaceObject && !i.extends && !i.legacyNamespace) {
+        printer.printLine("");
+        printer.printLine(`interface ${i.name} {`);
+        printer.increaseIndent();
+
+        emitProperty("", i, EmitScope.InstanceOnly, toStringTagProperty);
+
+        printer.decreaseIndent();
+        printer.printLine("}");
+      }
+    });
+
+    return printer.getResult();
+  }
+
   function emitES6DomIterators() {
     printer.reset();
     printer.printLine("/////////////////////////////");
diff --git a/src/test.ts b/src/test.ts
index 5cbc000de..4b9231a4e 100644
--- a/src/test.ts
+++ b/src/test.ts
@@ -110,55 +110,65 @@ function test() {
     compileGeneratedFiles(
       "es6",
       "dom.generated.d.ts",
+      "dom.tostringtag.generated.d.ts",
       "dom.iterable.generated.d.ts",
     ) &&
     compileGeneratedFiles(
       "es2018",
       "dom.generated.d.ts",
+      "dom.tostringtag.generated.d.ts",
       "dom.asynciterable.generated.d.ts",
     ) &&
     compileGeneratedFiles("es5", "webworker.generated.d.ts") &&
     compileGeneratedFiles(
       "es6",
       "webworker.generated.d.ts",
+      "webworker.tostringtag.generated.d.ts",
       "webworker.iterable.generated.d.ts",
     ) &&
     compileGeneratedFiles(
       "es2018",
       "webworker.generated.d.ts",
+      "webworker.tostringtag.generated.d.ts",
       "webworker.asynciterable.generated.d.ts",
     ) &&
     compileGeneratedFiles("es5", "sharedworker.generated.d.ts") &&
     compileGeneratedFiles(
       "es6",
       "sharedworker.generated.d.ts",
+      "sharedworker.tostringtag.generated.d.ts",
       "sharedworker.iterable.generated.d.ts",
     ) &&
     compileGeneratedFiles(
       "es2018",
       "sharedworker.generated.d.ts",
+      "sharedworker.tostringtag.generated.d.ts",
       "sharedworker.asynciterable.generated.d.ts",
     ) &&
     compileGeneratedFiles("es5", "serviceworker.generated.d.ts") &&
     compileGeneratedFiles(
       "es6",
       "serviceworker.generated.d.ts",
+      "serviceworker.tostringtag.generated.d.ts",
       "serviceworker.iterable.generated.d.ts",
     ) &&
     compileGeneratedFiles(
       "es2018",
       "serviceworker.generated.d.ts",
+      "serviceworker.tostringtag.generated.d.ts",
       "serviceworker.asynciterable.generated.d.ts",
     ) &&
     compileGeneratedFiles("es5", "audioworklet.generated.d.ts") &&
     compileGeneratedFiles(
       "es6",
       "audioworklet.generated.d.ts",
+      "audioworklet.tostringtag.generated.d.ts",
       "audioworklet.iterable.generated.d.ts",
     ) &&
     compileGeneratedFiles(
       "es2018",
       "audioworklet.generated.d.ts",
+      "audioworklet.tostringtag.generated.d.ts",
       "audioworklet.asynciterable.generated.d.ts",
     )
   ) {