<!--
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# Baseline Coverage

- web-features: [`v3.32.0`](https://github.com/web-platform-dx/web-features/releases/tag/v3.32.0)

## JavaScript Language (syntax)

- total: `43`
- mapped: `43`
- coverage: `100.0%`

| Feature ID | Name | Baseline | Year | Mapped | Mechanism | Delegates |
| --- | --- | --- | --- | --- | --- | --- |
| accessor-methods | ` Accessor methods ` | limited | - | ✅ | ` delegate ` | `es-x:no-legacy-object-prototype-accessor-methods` |
| arguments-callee | ` arguments.callee ` | limited | - | ✅ | ` delegate ` | `core:no-caller` |
| async-await | ` Async functions ` | widely | 2017 | ✅ | ` delegate ` | `es-x:no-async-functions` |
| async-generators | ` Async generators ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-async-iteration` |
| atomics-pause | ` Atomics.pause() ` | newly | 2025 | ✅ | ` self ` | `self:no-atomics-pause` |
| atomics-wait-async | ` Atomics.waitAsync() ` | newly | 2025 | ✅ | ` delegate ` | `es-x:no-atomics-waitasync` |
| bigint | ` BigInt ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-bigint` |
| bigint64array | ` BigInt64Array ` | widely | 2021 | ✅ | ` self ` | `self:no-bigint64array` |
| class-syntax | ` Classes ` | widely | 2016 | ✅ | ` delegate ` | `es-x:no-classes` |
| date-get-year-set-year | ` getYear() and setYear() ` | limited | - | ✅ | ` delegate ` | `es-x:no-date-prototype-getyear-setyear` |
| date-to-gmt-string | ` toGMTString() ` | limited | - | ✅ | ` delegate ` | `es-x:no-date-prototype-togmtstring` |
| destructuring | ` Destructuring ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-destructuring` |
| error-cause | ` Error cause ` | widely | 2021 | ✅ | ` delegate ` | `es-x:no-error-cause` |
| escape-unescape | ` escape() and unescape() ` | limited | - | ✅ | ` delegate ` | `es-x:no-escape-unescape` |
| exponentiation | ` Exponentiation operator ` | widely | 2017 | ✅ | ` delegate ` | `es-x:no-exponential-operators` |
| functions | ` Functions ` | widely | 2015 | ✅ | ` delegate ` | - |
| functions-caller-arguments | ` Function caller and arguments ` | limited | - | ✅ | ` self ` | `self:no-function-caller-arguments` |
| generators | ` Generators ` | widely | 2016 | ✅ | ` delegate ` | `es-x:no-generators` |
| globalthis | ` globalThis ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-global-this` |
| hashbang-comments | ` Hashbang comments ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-hashbang` |
| html-wrapper-methods | ` HTML wrapper methods ` | limited | - | ✅ | ` delegate ` | `es-x:no-string-create-html-methods` |
| is-error | ` Error.isError() ` | limited | - | ✅ | ` delegate ` | `es-x:no-error-iserror` |
| javascript | ` JavaScript (initial core language support) ` | widely | 2015 | ✅ | ` delegate ` | - |
| let-const | ` Let and const ` | widely | 2016 | ✅ | ` delegate ` | `es-x:no-block-scoped-variables` |
| logical-assignments | ` Logical assignments ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-logical-assignment-operators` |
| math-sum-precise | ` Math.sumPrecise() ` | newly | 2026 | ✅ | ` self ` | `self:no-math-sum-precise` |
| nullish-coalescing | ` Nullish coalescing ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-nullish-coalescing-operators` |
| numeric-separators | ` Numeric separators ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-numeric-separators` |
| object-hasown | ` Object.hasOwn() ` | widely | 2022 | ✅ | ` delegate ` | `es-x:no-object-hasown` |
| object-object | ` Object ` | widely | 2015 | ✅ | ` delegate ` | - |
| optional-catch-binding | ` Optional catch binding ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-optional-catch-binding` |
| proto | ` __proto__ ` | limited | - | ✅ | ` delegate ` | `core:no-proto` |
| proxy-reflect | ` Proxy and Reflect ` | widely | 2016 | ✅ | ` delegate ` | `es-x:no-proxy`, `es-x:no-reflect` |
| resizable-buffers | ` Resizable buffers ` | newly | 2024 | ✅ | ` delegate ` | - |
| shared-memory | ` SharedArrayBuffer and Atomics ` | widely | 2021 | ✅ | ` delegate ` | `es-x:no-shared-array-buffer`, `es-x:no-atomics` |
| spread | ` Spread syntax ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-spread-elements`, `es-x:no-rest-spread-properties` |
| template-literals | ` Template literals ` | widely | 2020 | ✅ | ` delegate ` | `es-x:no-template-literals` |
| temporal | ` Temporal ` | limited | - | ✅ | ` self ` | `self:no-temporal` |
| top-level-await | ` Top-level await ` | limited | - | ✅ | ` delegate ` | `es-x:no-top-level-await` |
| transferable-arraybuffer | ` Transferable ArrayBuffer ` | newly | 2024 | ✅ | ` delegate ` | `es-x:no-arraybuffer-prototype-transfer` |
| unicode-point-escapes | ` Unicode point escapes ` | widely | 2015 | ✅ | ` delegate ` | `es-x:no-unicode-codepoint-escapes` |
| weak-references | ` Weak references ` | widely | 2021 | ✅ | ` delegate ` | `es-x:no-weakrefs` |
| with | ` with ` | limited | - | ✅ | ` delegate ` | `core:no-with` |

## Web APIs (api.*)

- total: `532`
- excluded (out-of-scope): `22`
- included (in-scope): `510`
- mapped: `505`
- coverage: `99.0%`

| Feature ID | Name | Baseline | Year | Mapped | Patterns | Descriptors | Memo |
| --- | --- | --- | --- | --- | --- | --- | --- |
| a | ` <a> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 19 | - |
| abortable-fetch | ` Abortable fetch ` | widely | 2019 | ✅ | ` typed ` | 1 | - |
| aborting | ` AbortController and AbortSignal ` | widely | 2019 | ✅ | ` safe `, ` typed ` | 10 | - |
| abortsignal-any | ` AbortSignal.any() ` | newly | 2024 | ✅ | ` safe ` | 1 | - |
| abortsignal-timeout | ` AbortSignal.timeout() ` | newly | 2024 | ✅ | ` safe ` | 1 | - |
| accelerometer | ` Accelerometer ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| accesskey | ` accesskey ` | widely | 2015 | ✅ | ` typed ` | 2 | - |
| active-view-transition | ` Active view transition ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 12 | - |
| alerts | ` Alerts ` | widely | 2015 | ✅ | ` safe ` | 3 | - |
| ambient-light | ` Ambient light sensor ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| anchor-positioning | ` Anchor positioning ` | limited | - | ✅ | ` safe `, ` typed ` | 74 | - |
| angle-instanced-arrays | ` ANGLE_instanced_arrays WebGL extension ` | widely | 2016 | ✅ | ` safe `, ` typed ` | 6 | - |
| animations-css | ` Animations (CSS) ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 17 | - |
| app-file-handlers | ` File handlers ` | limited | - | ✅ | ` typed ` | 1 | - |
| app-launch-handler | ` Launch handler ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| aria-attribute-reflection | ` ARIA attribute reflection ` | widely | 2023 | ✅ | ` typed ` | 103 | - |
| arianotify | ` ariaNotify() ` | limited | - | ✅ | ` typed ` | 2 | - |
| async-clipboard | ` Async clipboard ` | newly | 2024 | ✅ | ` safe `, ` typed ` | 15 | - |
| async-iterable-streams | ` Asynchronously iterable streams ` | limited | - | ✅ | ` typed ` | 2 | - |
| attribution-reporting | ` Attribution reporting ` | limited | - | ✅ | ` typed ` | 5 | - |
| audio | ` <audio> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 2 | - |
| audio-session | ` Audio session ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| audio-video-tracks | ` Audio and video tracks ` | limited | - | ✅ | ` safe `, ` typed ` | 27 | - |
| audio-worklet | ` AudioWorklet ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 19 | - |
| audiolistener | ` AudioListener ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| audiolistener-setposition-setorientation | ` AudioListener setPosition() and setOrientation() ` | limited | - | ✅ | ` typed ` | 2 | - |
| autocapitalize | ` autocapitalize ` | limited | - | ✅ | ` typed ` | 1 | - |
| autocorrect | ` autocorrect ` | limited | - | ✅ | ` typed ` | 1 | - |
| autofocus | ` autofocus ` | widely | 2015 | ✅ | ` typed ` | 3 | - |
| autonomous-custom-elements | ` Autonomous custom elements ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 7 | - |
| background-fetch | ` Background fetch ` | limited | - | ✅ | ` safe `, ` typed ` | 31 | - |
| background-sync | ` Background sync ` | limited | - | ✅ | ` safe `, ` typed ` | 11 | - |
| badging | ` Badging ` | limited | - | ✅ | ` safe ` | 2 | - |
| barcode | ` Barcode detector ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| barprop | ` BarProp ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 8 | - |
| base | ` <base> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 3 | - |
| base64encodedecode | ` Base64 encoding and decoding ` | widely | 2016 | ✅ | ` safe `, ` typed ` | 4 | - |
| battery | ` Battery status ` | limited | - | ✅ | ` safe `, ` typed ` | 11 | - |
| beacons | ` Beacons ` | widely | 2018 | ✅ | ` safe ` | 1 | - |
| beforeinstallprompt | ` beforeinstallprompt ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| beforeunload | ` beforeunload ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| bfcache-blocking-reasons | ` Back/forward cache blocking reasons ` | limited | - | ✅ | ` safe `, ` typed ` | 12 | - |
| blocking-render | ` blocking=\ ` | limited | - | ✅ | ` typed ` | 3 | - |
| body | ` <body> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| br | ` <br> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| broadcast-channel | ` BroadcastChannel ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 7 | - |
| button | ` <button> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 12 | - |
| canvas | ` <canvas> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 6 | - |
| canvas-2d | ` 2D canvas ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 107 | - |
| canvas-2d-alpha | ` 2D canvas opacity ` | limited | - | ✅ | ` safe ` | 1 | - |
| canvas-2d-color-management | ` Color management for 2D canvas ` | limited | - | ✅ | ` safe ` | 1 | - |
| canvas-2d-desynchronized | ` Desynchronized 2D canvas ` | limited | - | ✅ | ` safe ` | 1 | - |
| canvas-2d-willreadfrequently | ` willReadFrequently ` | newly | 2024 | ✅ | ` safe ` | 1 | - |
| canvas-context-lost | ` contextlost and contextrestored ` | limited | - | ✅ | ` typed ` | 6 | - |
| canvas-createconicgradient | ` Canvas createConicGradient() ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| canvas-reset | ` Canvas reset() ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| canvas-roundrect | ` Canvas roundRect() ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| capture-handle | ` Capture Handle ` | limited | - | ✅ | ` typed ` | 3 | - |
| capture-stream-audio-video | ` captureStream() for <audio> and <video> ` | limited | - | ✅ | ` typed ` | 1 | - |
| capture-stream-canvas | ` captureStream() for <canvas> ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 4 | - |
| cascade-layers | ` Cascade layers ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 5 | - |
| change-event | ` Change event ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| channel-messaging | ` Channel messaging ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 11 | - |
| check-visibility | ` checkVisibility() ` | newly | 2024 | ✅ | ` typed ` | 1 | - |
| clip-path | ` clip-path ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 3 | - |
| clipboard-custom-format | ` Custom formats for clipboard items ` | limited | - | ✅ | ` typed ` | 1 | - |
| clipboard-events | ` Clipboard events ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 6 | - |
| clipboard-supports | ` ClipboardItem.supports() ` | newly | 2025 | ✅ | ` safe ` | 1 | - |
| clipboard-svg | ` SVG clipboard items ` | limited | - | ✅ | ` typed ` | 1 | - |
| clipboard-unsanitized-formats | ` Read unsanitized clipboard data ` | limited | - | ❌ | - | - | Permissioned/unsanitized data — not static-detectable |
| clipboardchange | ` clipboardchange ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| closewatcher | ` CloseWatcher ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| composed-ranges | ` Selection composed ranges ` | newly | 2025 | ✅ | ` typed ` | 1 | - |
| composition-events | ` Composition events ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 6 | - |
| compression-streams | ` Compression streams ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 8 | - |
| compute-pressure | ` CPU compute pressure ` | limited | - | ✅ | ` safe `, ` typed ` | 12 | - |
| console | ` Console ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 22 | - |
| constraint-validation | ` Constraint validation API ` | widely | 2018 | ✅ | ` safe `, ` typed ` | 56 | - |
| constructed-stylesheets | ` Constructed stylesheets ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 5 | - |
| contact-picker | ` Contact picker ` | limited | - | ✅ | ` safe `, ` typed ` | 16 | - |
| container-queries | ` Container queries ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 3 | - |
| content-index | ` Content Index ` | limited | - | ✅ | ` safe `, ` typed ` | 9 | - |
| content-visibility | ` content-visibility ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 4 | - |
| contenteditable | ` contenteditable ` | widely | 2015 | ✅ | ` typed ` | 2 | - |
| contenteditable-plaintextonly | ` contenteditable=\ ` | newly | 2025 | ❌ | - | - | HTML attribute — use `html-eslint` |
| controls-list | ` controlslist ` | limited | - | ✅ | ` typed ` | 1 | - |
| cookie-enabled | ` cookieEnabled ` | newly | 2024 | ✅ | ` safe ` | 1 | - |
| cookie-store | ` Cookie store ` | limited | - | ✅ | ` safe `, ` typed ` | 22 | - |
| cookies | ` Cookies ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| counter-style | ` @counter-style ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 12 | - |
| createimagebitmap | ` createImageBitmap ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 12 | - |
| credential-management | ` Credential management ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 10 | - |
| cross-document-view-transitions | ` Cross-document view transitions ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| csp | ` Content Security Policy (CSP) ` | widely | 2016 | ✅ | ` safe `, ` typed ` | 20 | - |
| css-escape | ` CSS.escape() ` | widely | 2020 | ✅ | ` safe ` | 1 | - |
| css-object-model | ` CSS object model ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 80 | - |
| css-object-model-discouraged | ` CSS object model (DOM level 2) ` | limited | - | ✅ | ` safe `, ` typed ` | 24 | - |
| css-supports | ` CSS.supports() ` | widely | 2020 | ✅ | ` safe ` | 1 | - |
| css-typed-om | ` CSS typed object model ` | limited | - | ✅ | ` safe `, ` typed ` | 132 | - |
| custom-media-queries | ` Custom media queries ` | limited | - | ✅ | ` safe ` | 1 | CSS at-rule — use stylelint |
| customized-built-in-elements | ` Customized built-in elements ` | limited | - | ✅ | ` typed ` | 1 | - |
| data | ` <data> ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 2 | - |
| datalist | ` <datalist> ` | limited | - | ✅ | ` safe `, ` typed ` | 2 | - |
| dataset | ` Dataset ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 4 | - |
| declarative-shadow-dom | ` Declarative shadow DOM ` | newly | 2024 | ✅ | ` typed ` | 5 | - |
| dedicated-workers | ` Dedicated workers ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 28 | - |
| del | ` <del> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 3 | - |
| description-list | ` Description list ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML semantics — use `html-eslint` |
| details | ` <details> ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 3 | - |
| details-name | ` Mutually exclusive <details> elements ` | newly | 2024 | ✅ | ` typed ` | 1 | - |
| device-memory | ` Device memory ` | limited | - | ✅ | ` safe `, ` typed ` | 2 | - |
| device-orientation-events | ` Device orientation events ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 25 | - |
| device-posture | ` Device posture ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| devicepixelratio | ` devicePixelRatio ` | limited | - | ✅ | ` safe ` | 1 | - |
| dialog | ` <dialog> ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 8 | - |
| dialog-closedby | ` <dialog closedby> ` | limited | - | ✅ | ` typed ` | 1 | - |
| digital-credentials | ` Digital credentials ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| digital-goods | ` Digital goods ` | limited | - | ✅ | ` safe ` | 1 | - |
| dirname | ` dirname ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| div | ` <div> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| document-caretpositionfrompoint | ` document.caretPositionFromPoint() ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 5 | - |
| document-colors | ` Document colors ` | limited | - | ✅ | ` typed ` | 5 | - |
| document-picture-in-picture | ` Document picture-in-picture ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| document-write | ` document.write() ` | limited | - | ✅ | ` typed ` | 4 | - |
| dom | ` DOM ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 277 | - |
| dom-geometry | ` DOM Geometry ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 140 | - |
| domparser | ` DOMParser ` | widely | 2016 | ✅ | ` safe `, ` typed ` | 3 | - |
| download | ` download ` | widely | 2019 | ✅ | ` typed ` | 3 | - |
| draganddrop | ` Drag and Drop ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 33 | - |
| edit-context | ` EditContext ` | limited | - | ✅ | ` safe `, ` typed ` | 39 | - |
| element-capture | ` Element capture ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| element-from-point | ` document.elementFromPoint() and document.elementsFromPoint() ` | widely | 2020 | ✅ | ` typed ` | 2 | - |
| element-timing | ` Element timing ` | limited | - | ✅ | ` safe `, ` typed ` | 12 | - |
| embed | ` <embed> ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 6 | - |
| encrypted-media-extensions | ` Encrypted media extensions ` | widely | 2019 | ✅ | ` safe `, ` typed ` | 42 | - |
| enterkeyhint | ` enterkeyhint ` | widely | 2021 | ✅ | ` typed ` | 1 | - |
| event-timing | ` Event timing ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 17 | - |
| events | ` Events ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 23 | - |
| execcommand | ` execCommand() ` | limited | - | ✅ | ` typed ` | 6 | - |
| ext-blend-minmax | ` EXT_blend_minmax WebGL extension ` | widely | 2018 | ✅ | ` safe ` | 3 | - |
| ext-color-buffer-float | ` EXT_color_buffer_float WebGL extension ` | widely | 2021 | ✅ | ` safe ` | 3 | - |
| ext-color-buffer-half-float | ` EXT_color_buffer_half_float WebGL extension ` | widely | 2020 | ✅ | ` safe ` | 3 | - |
| ext-disjoint-timer-query | ` EXT_disjoint_timer_query WebGL extension ` | limited | - | ✅ | ` safe `, ` typed ` | 12 | - |
| ext-float-blend | ` EXT_float_blend WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| ext-frag-depth | ` EXT_frag_depth WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| ext-shader-texture-lod | ` EXT_shader_texture_lod WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| ext-srgb | ` EXT_sRGB WebGL extension ` | widely | 2020 | ✅ | ` safe ` | 3 | - |
| ext-texture-compression-bptc | ` EXT_texture_compression_bptc WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| ext-texture-compression-rgtc | ` EXT_texture_compression_rgtc WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| ext-texture-filter-anisotropic | ` EXT_texture_filter_anisotropic WebGL extension ` | widely | 2016 | ✅ | ` safe ` | 3 | - |
| ext-texture-norm16 | ` EXT_texture_norm16 WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| external | ` window.external ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| eyedropper | ` Eyedropper ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| fast-seek | ` fastSeek() ` | limited | - | ✅ | ` typed ` | 1 | - |
| feature-policy | ` Feature policy ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| fedcm | ` Federated credential management ` | limited | - | ✅ | ` safe `, ` typed ` | 2 | - |
| federated-credentials | ` Federated credentials ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| fencedframe | ` <fencedframe> ` | limited | - | ✅ | ` safe `, ` typed ` | 14 | - |
| fetch | ` Fetch ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 61 | - |
| fetch-formdata | ` Fetch form data ` | limited | - | ✅ | ` typed ` | 2 | - |
| fetch-priority | ` Fetch priority ` | newly | 2024 | ✅ | ` typed ` | 3 | - |
| fetch-request-streams | ` Fetch upload streams ` | limited | - | ✅ | ` typed ` | 1 | - |
| fetchlater | ` fetchLater ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| fieldset | ` <fieldset> and <legend> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 8 | - |
| file | ` File API ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 40 | - |
| file-system-access | ` File system access ` | limited | - | ✅ | ` safe `, ` typed ` | 11 | - |
| focus-events | ` Focus events ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 9 | - |
| font-face | ` @font-face ` | widely | 2016 | ✅ | ` safe `, ` typed ` | 2 | - |
| font-loading | ` Font loading ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 40 | - |
| font-metric-overrides | ` Font metric overrides ` | limited | - | ✅ | ` typed ` | 3 | - |
| font-palette | ` font-palette ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 5 | - |
| font-variant-alternates | ` font-variant-alternates ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 20 | - |
| font-width | ` font-width ` | limited | - | ✅ | ` typed ` | 1 | - |
| form | ` <form> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 28 | - |
| form-associated-custom-elements | ` Form-associated custom elements ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 11 | - |
| fullscreen | ` Fullscreen API ` | limited | - | ✅ | ` typed ` | 10 | - |
| function | ` @function ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| gamepad | ` Gamepad ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 17 | - |
| gamepad-haptics | ` Gamepad haptic feedback ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| gamepad-touch | ` Gamepad touch buttons ` | limited | - | ✅ | ` typed ` | 1 | - |
| gamepad-vr | ` Gamepad VR hands and poses ` | limited | - | ✅ | ` safe `, ` typed ` | 11 | - |
| geolocation | ` Geolocation API ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 26 | - |
| geolocation-element | ` <geolocation> ` | limited | - | ✅ | ` safe `, ` typed ` | 14 | - |
| get-computed-style | ` getComputedStyle() ` | widely | 2015 | ✅ | ` safe ` | 1 | - |
| getallrecords | ` IndexedDB getAllRecords() ` | limited | - | ✅ | ` typed ` | 2 | - |
| getboxquads | ` getBoxQuads() ` | limited | - | ✅ | ` typed ` | 3 | - |
| gethtml | ` getHTML() ` | newly | 2024 | ✅ | ` typed ` | 2 | - |
| gpc | ` Global privacy control ` | limited | - | ✅ | ` safe `, ` typed ` | 2 | - |
| gyroscope | ` Gyroscope ` | limited | - | ✅ | ` safe `, ` typed ` | 6 | - |
| hardware-concurrency | ` hardwareConcurrency ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 2 | - |
| hashchange | ` hashchange ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 5 | - |
| head | ` <head> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| headings | ` <h1> through <h6> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML headings — use `html-eslint` |
| hidden-until-found | ` hidden=\ ` | limited | - | ✅ | ` typed ` | 1 | - |
| highlight | ` Custom highlights ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 27 | - |
| highlightsfrompoint | ` Custom highlights from point ` | limited | - | ✅ | ` typed ` | 1 | - |
| history | ` History ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 15 | - |
| hr | ` <hr> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| html | ` <html> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| html-media-capture | ` HTML media capture ` | limited | - | ✅ | ` typed ` | 1 | - |
| idle-detection | ` Idle detection ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| iframe | ` <iframe> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 8 | - |
| iframe-credentialless | ` Credentialless iframes ` | limited | - | ✅ | ` safe `, ` typed ` | 2 | - |
| iframe-sandbox | ` Sandboxed iframes ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| iframe-srcdoc | ` srcdoc ` | widely | 2020 | ✅ | ` typed ` | 1 | - |
| image-maps | ` Image maps ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 24 | - |
| imagebitmaprenderingcontext | ` ImageBitmapRenderingContext ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 3 | - |
| img | ` <img> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 14 | - |
| import | ` @import ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 4 | - |
| indexeddb | ` IndexedDB ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 111 | - |
| inert | ` inert ` | widely | 2023 | ✅ | ` typed ` | 1 | - |
| ink | ` Ink ` | limited | - | ✅ | ` safe `, ` typed ` | 6 | - |
| input | ` <input> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 36 | - |
| input-checkbox | ` <input type=\ ` | widely | 2015 | ✅ | ` typed ` | 2 | - |
| input-color-alpha | ` alpha and colorspace attributes for <input type=color> ` | limited | - | ✅ | ` typed ` | 2 | - |
| input-date-time | ` Date and time <input> types ` | widely | 2021 | ✅ | ` typed ` | 1 | - |
| input-event | ` input (event) ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 9 | - |
| input-file | ` <input type=\ ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| input-file-multiple | ` <input type=\ ` | widely | 2015 | ✅ | ` typed ` | 2 | - |
| input-file-webkitdirectory | ` <input type=\ ` | newly | 2025 | ✅ | ` typed ` | 2 | - |
| input-image | ` <input type=\ ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| input-number | ` <input type=\ ` | widely | 2015 | ✅ | ` typed ` | 6 | - |
| inputmode | ` inputmode ` | widely | 2021 | ✅ | ` typed ` | 1 | - |
| insertable-streams | ` Insertable streams for MediaStreamTrack ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| interest-invokers | ` Interest invokers ` | limited | - | ✅ | ` safe `, ` typed ` | 9 | - |
| intersection-observer | ` Intersection observer ` | widely | 2019 | ✅ | ` safe `, ` typed ` | 22 | - |
| invoker-commands | ` Invoker commands ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 7 | - |
| is-input-pending | ` isInputPending() ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| is-secure-context | ` isSecureContext ` | widely | 2018 | ✅ | ` safe `, ` typed ` | 2 | - |
| js-modules | ` JavaScript modules ` | widely | 2018 | ✅ | ` typed ` | 1 | - |
| js-modules-service-workers | ` JavaScript modules in service workers ` | newly | 2026 | ✅ | ` typed ` | 1 | - |
| js-modules-shared-workers | ` JavaScript modules in shared workers ` | newly | 2026 | ✅ | ` safe ` | 1 | - |
| js-modules-workers | ` JavaScript modules in workers ` | widely | 2023 | ✅ | ` safe ` | 1 | - |
| keyboard-events | ` Keyboard events ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 14 | - |
| keyboard-lock | ` Keyboard lock ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| keyboard-map | ` Keyboard map ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| khr-parallel-shader-compile | ` KHR_parallel_shader_compile WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| label | ` <label> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 4 | - |
| lang-attr | ` lang ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| language | ` Language ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 6 | - |
| languagedetector | ` Language detector ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| languagemodel | ` LanguageModel ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| largest-contentful-paint | ` Largest contentful paint (LCP) ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 8 | - |
| layout-instability | ` Layout instability ` | limited | - | ✅ | ` safe `, ` typed ` | 11 | - |
| link | ` <link> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 11 | - |
| link-rel-prefetch | ` <link rel=\ ` | limited | - | ❌ | - | - | HTML link rel — use `html-eslint` |
| list-elements | ` <ol>, <ul>, and <li> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 7 | - |
| loading-lazy | ` Lazy-loading images and iframes ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| loading-lazy-media | ` Lazy-loading media ` | limited | - | ✅ | ` typed ` | 1 | - |
| local-fonts | ` Local fonts ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| local-network-access | ` Local network access ` | limited | - | ✅ | ` typed ` | 1 | - |
| localstorage | ` localStorage and sessionStorage ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 17 | - |
| location | ` Location ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 17 | - |
| long-animation-frames | ` Long animation frames ` | limited | - | ✅ | ` safe `, ` typed ` | 19 | - |
| longtasks | ` Long tasks ` | limited | - | ✅ | ` safe `, ` typed ` | 9 | - |
| magnetometer | ` Magnetometer ` | limited | - | ✅ | ` safe `, ` typed ` | 6 | - |
| managed-media-source | ` Managed media source ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| matchmedia | ` matchMedia ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 10 | - |
| mathml | ` MathML ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 7 | - |
| measure-memory | ` Memory measurement ` | limited | - | ✅ | ` typed ` | 1 | - |
| media-capabilities | ` Media capabilities ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 5 | - |
| media-capture | ` Media capture ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 51 | - |
| media-playback-quality | ` Media playback quality ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 5 | - |
| media-session | ` Media session ` | limited | - | ✅ | ` safe `, ` typed ` | 20 | - |
| media-source | ` Media source ` | limited | - | ✅ | ` safe `, ` typed ` | 50 | - |
| mediacontroller | ` MediaController ` | limited | - | ✅ | ` safe `, ` typed ` | 17 | - |
| mediastream-recording | ` MediaStream recording ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 24 | - |
| menu | ` <menu> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| messageerror | ` messageerror ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 6 | - |
| meta | ` <meta> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 5 | - |
| meter | ` <meter> ` | widely | 2018 | ✅ | ` safe `, ` typed ` | 8 | - |
| mouse-events | ` Mouse events ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 34 | - |
| move-before | ` moveBefore() ` | limited | - | ✅ | ` typed ` | 3 | - |
| mutation-events | ` Mutation events ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| mutationobserver | ` MutationObserver ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 15 | - |
| namespace | ` @namespace ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 3 | - |
| navigation | ` Navigation API ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 59 | - |
| navigation-precommit-handlers | ` Navigation precommit handlers ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| navigation-timing | ` Navigation timing ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 13 | - |
| navigation-timing-confidence | ` Navigation timing confidence ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| navigator | ` Navigator ` | widely | 2015 | ✅ | ` safe ` | 2 | - |
| nesting | ` Nesting ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 5 | - |
| network-information | ` Network Information ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| non-cookie-storage-access | ` Non-cookie storage access ` | limited | - | ✅ | ` safe `, ` typed ` | 13 | - |
| notifications | ` Notifications ` | limited | - | ✅ | ` safe `, ` typed ` | 36 | - |
| numeric-factory-functions | ` Numeric factory functions ` | limited | - | ✅ | ` safe ` | 63 | - |
| object | ` <object> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 10 | - |
| observable | ` Observable ` | limited | - | ✅ | ` safe `, ` typed ` | 30 | - |
| oes-element-index-uint | ` OES_element_index_uint WebGL extension ` | widely | 2015 | ✅ | ` safe ` | 3 | - |
| oes-fbo-render-mipmap | ` OES_fbo_render_mipmap WebGL extension ` | widely | 2021 | ✅ | ` safe ` | 3 | - |
| oes-standard-derivatives | ` OES_standard_derivatives WebGL extension ` | widely | 2015 | ✅ | ` safe ` | 3 | - |
| oes-texture-float | ` OES_texture_float WebGL extension ` | widely | 2015 | ✅ | ` safe ` | 3 | - |
| oes-texture-float-linear | ` OES_texture_float_linear WebGL extension ` | widely | 2015 | ✅ | ` safe ` | 3 | - |
| oes-texture-half-float | ` OES_texture_half_float WebGL extension ` | widely | 2016 | ✅ | ` safe ` | 3 | - |
| oes-texture-half-float-linear | ` OES_texture_half_float_linear WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| oes-vertex-array-object | ` OES_vertex_array_object WebGL extension ` | widely | 2018 | ✅ | ` safe `, ` typed ` | 8 | - |
| offline-audio-context | ` OfflineAudioContext ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 10 | - |
| offscreen-canvas | ` Offscreen canvas ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 75 | - |
| online | ` Online status ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 6 | - |
| orientation-sensor | ` Orientation Sensor ` | limited | - | ✅ | ` safe `, ` typed ` | 19 | - |
| origin | ` Origin ` | limited | - | ✅ | ` safe `, ` typed ` | 6 | - |
| origin-private-file-system | ` Origin private file system ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 23 | - |
| output | ` <output> ` | widely | - | ✅ | ` safe `, ` typed ` | 9 | - |
| ovr-multiview2 | ` OVR_multiview2 WebGL extension ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| p | ` <p> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| page-lifecycle | ` Page lifecycle ` | limited | - | ✅ | ` typed ` | 3 | - |
| page-transition-events | ` Page transition events ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 5 | - |
| page-visibility | ` Page visibility ` | widely | 2015 | ✅ | ` typed ` | 3 | - |
| page-visibility-state | ` Page visibility state ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| paint | ` paint() ` | limited | - | ✅ | ` safe `, ` typed ` | 48 | - |
| paint-timing | ` Paint timing ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 4 | - |
| parse-html-unsafe | ` Unsanitized HTML parsing methods ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 3 | - |
| partitioned-cookies | ` Partitioned cookies ` | limited | - | ❌ | - | - | Storage/partitioning semantics — not static-detectable |
| password-credentials | ` Password credentials ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| payment-handler | ` Payment handler ` | limited | - | ✅ | ` safe `, ` typed ` | 26 | - |
| payment-request | ` Payment request ` | limited | - | ✅ | ` safe `, ` typed ` | 28 | - |
| pdf-viewer | ` pdfViewerEnabled ` | widely | 2023 | ✅ | ` safe ` | 2 | - |
| performance | ` Performance ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 36 | - |
| performancetiming | ` PerformanceTiming and PerformanceNavigation ` | limited | - | ✅ | ` safe `, ` typed ` | 29 | - |
| periodic-background-sync | ` Periodic background sync ` | limited | - | ✅ | ` safe `, ` typed ` | 9 | - |
| permissions | ` Permissions ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 9 | - |
| permissions-policy | ` Permissions policy ` | limited | - | ✅ | ` typed ` | 1 | - |
| picture | ` <picture> ` | widely | 2016 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| picture-in-picture | ` Picture-in-picture (video) ` | limited | - | ✅ | ` safe `, ` typed ` | 15 | - |
| ping | ` ping ` | limited | - | ✅ | ` typed ` | 3 | - |
| pointer-events-api | ` Pointer Events ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 32 | - |
| pointer-lock | ` Pointer lock ` | limited | - | ✅ | ` typed ` | 5 | - |
| popover | ` Popover ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 13 | - |
| popover-hint | ` popover=\ ` | limited | - | ❌ | - | - | HTML attribute — use `html-eslint` |
| postmessage | ` postMessage ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 12 | - |
| pre | ` <pre> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| preloading-responsive-images | ` Preloading responsive images ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| presentation-api | ` Presentation API ` | limited | - | ✅ | ` safe `, ` typed ` | 38 | - |
| preserves-pitch | ` preservesPitch ` | widely | 2023 | ✅ | ` typed ` | 1 | - |
| print | ` window.print() ` | widely | 2023 | ✅ | ` safe ` | 1 | - |
| print-events | ` Print events ` | widely | 2019 | ✅ | ` safe ` | 2 | - |
| private-click-measurement | ` Private click measurement ` | limited | - | ✅ | ` typed ` | 1 | - |
| profiler | ` Profiler ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| progress | ` <progress> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 5 | - |
| protected-audience | ` Protected audience ` | limited | - | ✅ | ` safe `, ` typed ` | 14 | - |
| push | ` Push messages ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 33 | - |
| q | ` <q> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 2 | - |
| queuemicrotask | ` queueMicrotask() ` | widely | 2020 | ✅ | ` safe ` | 1 | - |
| readable-byte-streams | ` Readable byte streams ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 16 | - |
| readablestream-from | ` ReadableStream.from() ` | limited | - | ✅ | ` safe ` | 1 | - |
| referencetarget | ` Reference target ` | limited | - | ✅ | ` typed ` | 2 | - |
| referrer-policy | ` Referrer policy ` | widely | 2021 | ✅ | ` typed ` | 6 | - |
| region-capture | ` Region capture ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| registered-custom-properties | ` Registered custom properties ` | newly | 2024 | ✅ | ` safe `, ` typed ` | 6 | - |
| registerprotocolhandler | ` registerProtocolHandler ` | limited | - | ✅ | ` safe ` | 2 | - |
| related-apps | ` Related apps ` | limited | - | ✅ | ` safe ` | 1 | - |
| related-website-sets | ` Related website sets ` | limited | - | ✅ | ` typed ` | 2 | - |
| remote-playback | ` Remote playback ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| reporting | ` Reporting API ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 6 | - |
| reporting-coep-violations | ` COEP violation reports ` | limited | - | ❌ | - | - | - |
| reporting-crashes-storage | ` Crash report storage ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| reporting-csp-violations | ` CSP violation reports ` | newly | 2026 | ❌ | - | - | - |
| reporting-deprecation | ` Deprecation reports ` | limited | - | ❌ | - | - | - |
| reporting-integrity-violations | ` Integrity violation reports ` | limited | - | ❌ | - | - | - |
| reporting-interventions | ` Intervention reports ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| reporting-permissions-policy-violations | ` Permissions policy violation reporting ` | limited | - | ❌ | - | - | - |
| request-animation-frame | ` requestAnimationFrame() ` | widely | 2015 | ✅ | ` safe ` | 2 | - |
| request-animation-frame-workers | ` requestAnimationFrame() in workers ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| request-video-frame-callback | ` requestVideoFrameCallback() ` | newly | 2024 | ✅ | ` typed ` | 2 | - |
| requestclose | ` dialog.requestClose() ` | newly | 2025 | ✅ | ` typed ` | 1 | - |
| requestidlecallback | ` requestIdleCallback() ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| resize-observer | ` Resize observer ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 14 | - |
| resource-size | ` Resource size ` | widely | 2023 | ✅ | ` typed ` | 3 | - |
| resource-timing | ` Resource timing ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 25 | - |
| sanitizer | ` Sanitizer API ` | limited | - | ✅ | ` safe `, ` typed ` | 14 | - |
| savedata | ` Save-Data ` | limited | - | ✅ | ` typed ` | 1 | - |
| scheduler | ` Scheduler API ` | limited | - | ✅ | ` safe `, ` typed ` | 14 | - |
| scope | ` @scope ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 3 | - |
| scoped-custom-element-registries | ` Scoped custom element registries ` | limited | - | ✅ | ` safe `, ` typed ` | 6 | - |
| screen | ` Screen ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 7 | - |
| screen-capture | ` Screen capture ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| screen-orientation | ` Screen orientation ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 5 | - |
| screen-orientation-lock | ` Screen orientation lock ` | limited | - | ✅ | ` typed ` | 2 | - |
| screen-wake-lock | ` Screen wake lock ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 9 | - |
| script | ` <script> and <noscript> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 10 | - |
| scroll-driven-animations | ` Scroll-driven animations ` | limited | - | ✅ | ` safe `, ` typed ` | 9 | - |
| scroll-elements | ` Scroll methods on elements ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 15 | - |
| scroll-into-view | ` scrollIntoView() ` | widely | 2020 | ✅ | ` typed ` | 1 | - |
| scroll-into-view-container | ` scrollIntoView() container ` | limited | - | ❌ | - | - | Option detection requires typed receiver validation (Element.scrollIntoView) — future enhancement |
| scroll-snap-events | ` Scroll snap events ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| scroll-to-text-fragment | ` Scroll to text fragment ` | newly | 2024 | ✅ | ` safe `, ` typed ` | 2 | - |
| scrollend | ` scrollend ` | newly | 2025 | ✅ | ` typed ` | 2 | - |
| secure-payment-confirmation | ` Secure payment confirmation ` | limited | - | ✅ | ` safe ` | 1 | - |
| select | ` <select> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 32 | - |
| selection-api | ` Selection ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 76 | - |
| serial | ` Web serial ` | limited | - | ✅ | ` safe `, ` typed ` | 17 | - |
| serializable-errors | ` Serializable errors ` | limited | - | ✅ | ` typed ` | 1 | - |
| server-sent-events | ` Server-sent events ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 10 | - |
| server-timing | ` Server timing ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 6 | - |
| service-workers | ` Service workers ` | widely | 2018 | ✅ | ` safe `, ` typed ` | 95 | - |
| service-workers-static-routes | ` Service workers static routing ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| setinterval | ` setInterval ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 5 | - |
| settimeout | ` setTimeout() ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 5 | - |
| shadow-dom | ` Shadow DOM ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 12 | - |
| shadow-parts | ` Shadow parts ` | widely | 2020 | ✅ | ` typed ` | 1 | - |
| share | ` navigator.share() ` | limited | - | ✅ | ` safe ` | 2 | - |
| shared-storage | ` Shared storage ` | limited | - | ✅ | ` safe `, ` typed ` | 19 | - |
| shared-storage-locks | ` Shared storage locks ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| shared-workers | ` Shared worker ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 8 | - |
| show-picker-input | ` showPicker() for <input> ` | limited | - | ✅ | ` typed ` | 1 | - |
| show-picker-select | ` showPicker() for <select> ` | limited | - | ✅ | ` typed ` | 1 | - |
| slot | ` <slot> ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 8 | - |
| slot-assign | ` Imperative slot assignment ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| smil-svg-animations | ` SMIL SVG animations ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 62 | - |
| span | ` <span> ` | widely | 2015 | ✅ | ` safe ` | 1 | HTML element — use `html-eslint` |
| speculation-rules | ` Speculation rules ` | limited | - | ✅ | ` typed ` | 3 | - |
| speech-recognition | ` Speech recognition ` | limited | - | ✅ | ` safe `, ` typed ` | 38 | - |
| speech-recognition-grammar | ` Speech recognition grammar ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| speech-synthesis | ` Speech synthesis ` | widely | 2018 | ✅ | ` safe `, ` typed ` | 42 | - |
| spellcheck | ` spellcheck ` | widely | 2017 | ✅ | ` typed ` | 1 | - |
| srcset | ` srcset and sizes ` | widely | 2017 | ✅ | ` typed ` | 4 | - |
| starting-style | ` @starting-style ` | newly | 2024 | ✅ | ` safe ` | 1 | CSS at-rule — use stylelint |
| state | ` :state() ` | newly | 2024 | ✅ | ` safe `, ` typed ` | 12 | - |
| storage-access | ` Storage access ` | widely | 2023 | ✅ | ` typed ` | 3 | - |
| storage-buckets | ` Storage buckets ` | limited | - | ✅ | ` safe `, ` typed ` | 16 | - |
| storage-manager | ` Storage manager ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 7 | - |
| streams | ` Streams ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 54 | - |
| structured-clone | ` structuredClone() ` | widely | 2022 | ✅ | ` safe ` | 1 | - |
| style | ` <style> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 3 | - |
| subresource-integrity | ` Subresource integrity ` | widely | 2018 | ✅ | ` typed ` | 3 | - |
| summarizer | ` Summarizer ` | limited | - | ✅ | ` safe `, ` typed ` | 15 | - |
| supports | ` @supports ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 2 | - |
| svg | ` SVG ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 299 | - |
| svg-discouraged | ` SVG 1.1 ` | limited | - | ✅ | ` safe `, ` typed ` | 33 | - |
| svg-filters | ` SVG filters ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 202 | - |
| tabindex | ` tabindex ` | widely | 2018 | ✅ | ` typed ` | 1 | - |
| table | ` Tables ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 35 | - |
| table-discouraged | ` Table styling ` | limited | - | ✅ | ` typed ` | 33 | - |
| template | ` <template> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 2 | - |
| text-encoding | ` Text encoding and decoding ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 25 | - |
| text-tracks | ` Text tracks ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 40 | - |
| textarea | ` <textarea> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 25 | - |
| time | ` <time> ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 2 | - |
| title | ` <title> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 2 | - |
| title-attr | ` title (attribute) ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| toggleevent-source | ` ToggleEvent source ` | newly | 2026 | ✅ | ` typed ` | 1 | - |
| topics | ` Topics ` | limited | - | ✅ | ` typed ` | 2 | - |
| touch-events | ` Touch events ` | limited | - | ✅ | ` safe `, ` typed ` | 33 | - |
| transferable-streams | ` Transferable streams ` | limited | - | ✅ | ` typed ` | 3 | - |
| transformstream-transformer-cancel | ` TransformStream transformer cancel() method ` | limited | - | ✅ | ` safe ` | 1 | - |
| transitions | ` Transitions (CSS) ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 11 | - |
| translate | ` translate ` | widely | 2023 | ✅ | ` typed ` | 1 | - |
| translator | ` Translator ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| trusted-types | ` Trusted types ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 27 | - |
| ua-client-hints | ` User agent client hints ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| url | ` URL ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 33 | - |
| url-canparse | ` URL.canParse() ` | widely | 2023 | ✅ | ` safe ` | 1 | - |
| urlpattern | ` URLPattern ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 13 | - |
| user-activation | ` User activation ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 4 | - |
| user-agent-sniffing | ` User agent sniffing ` | widely | 2016 | ✅ | ` safe `, ` typed ` | 17 | - |
| vibration | ` Vibration ` | limited | - | ✅ | ` safe ` | 1 | - |
| video | ` <video> ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 65 | - |
| view-transitions | ` View transitions ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 15 | - |
| view-transitions-element-scoped | ` Element-scoped view transitions ` | limited | - | ✅ | ` typed ` | 3 | - |
| viewport-segments | ` Viewport segments ` | limited | - | ✅ | ` safe `, ` typed ` | 3 | - |
| virtual-keyboard | ` Virtual keyboard ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| visual-viewport | ` Visual viewport API ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 12 | - |
| web-animations | ` Web animations ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 54 | - |
| web-animations-iterationcomposite | ` iterationComposite ` | limited | - | ✅ | ` typed ` | 1 | - |
| web-audio | ` Web Audio ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 187 | - |
| web-bluetooth | ` Web Bluetooth ` | limited | - | ✅ | ` safe `, ` typed ` | 57 | - |
| web-cryptography | ` Web Cryptography ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 26 | - |
| web-locks | ` Locks ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 8 | - |
| web-midi | ` Web MIDI ` | limited | - | ✅ | ` safe `, ` typed ` | 47 | - |
| web-nfc | ` Web NFC ` | limited | - | ✅ | ` safe `, ` typed ` | 27 | - |
| web-otp | ` WebOTP ` | limited | - | ✅ | ` safe `, ` typed ` | 2 | - |
| webauthn | ` Web authentication ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 20 | - |
| webauthn-public-key-easy | ` Web authentication easy public key access ` | widely | 2023 | ✅ | ` typed ` | 3 | - |
| webauthn-signals | ` Web authentication signal methods ` | limited | - | ✅ | ` safe ` | 3 | - |
| webcodecs | ` WebCodecs ` | limited | - | ✅ | ` safe `, ` typed ` | 115 | - |
| webdriver | ` WebDriver ` | limited | - | ✅ | ` safe ` | 1 | - |
| webgl | ` WebGL ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 175 | - |
| webgl-color-buffer-float | ` WEBGL_color_buffer_float WebGL extension ` | widely | 2021 | ✅ | ` safe ` | 3 | - |
| webgl-color-management | ` Color management for WebGL ` | newly | 2024 | ✅ | ` typed ` | 2 | - |
| webgl-compressed-texture-astc | ` WEBGL_compressed_texture_astc WebGL extension ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 4 | - |
| webgl-compressed-texture-etc | ` WEBGL_compressed_texture_etc WebGL extension ` | widely | 2020 | ✅ | ` safe ` | 3 | - |
| webgl-compressed-texture-etc1 | ` WEBGL_compressed_texture_etc1 WebGL extension ` | widely | 2020 | ✅ | ` safe ` | 3 | - |
| webgl-compressed-texture-pvrtc | ` WEBGL_compressed_texture_pvrtc WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| webgl-compressed-texture-s3tc | ` WEBGL_compressed_texture_s3tc WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| webgl-compressed-texture-s3tc-srgb | ` WEBGL_compressed_texture_s3tc_srgb WebGL extension ` | limited | - | ✅ | ` safe ` | 3 | - |
| webgl-debug-renderer-info | ` WEBGL_debug_renderer_info WebGL extension ` | widely | 2017 | ✅ | ` safe ` | 3 | - |
| webgl-debug-shaders | ` WEBGL_debug_shaders WebGL extension ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 4 | - |
| webgl-depth-texture | ` WEBGL_depth_texture WebGL extension ` | widely | 2015 | ✅ | ` safe ` | 3 | - |
| webgl-desynchronized | ` Desynchronized WebGL canvas ` | limited | - | ✅ | ` safe ` | 1 | - |
| webgl-draw-buffers | ` WEBGL_draw_buffers WebGL extension ` | limited | - | ✅ | ` safe `, ` typed ` | 4 | - |
| webgl-lose-context | ` WEBGL_lose_context WebGL extension ` | widely | 2018 | ✅ | ` safe `, ` typed ` | 5 | - |
| webgl-multi-draw | ` WEBGL_multi_draw WebGL extension ` | limited | - | ✅ | ` safe `, ` typed ` | 7 | - |
| webgl-oes-draw-buffers-indexed | ` OES_draw_buffers_indexed WebGL extension ` | widely | 2022 | ✅ | ` safe `, ` typed ` | 10 | - |
| webgl-sab | ` SharedArrayBuffer in WebGL ` | limited | - | ❌ | - | - | SAB requires COOP/COEP — environment dependent |
| webgl2 | ` WebGL2 ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 235 | - |
| webgl2-color-management | ` Color management for WebGL2 ` | newly | 2024 | ✅ | ` typed ` | 2 | - |
| webgl2-desynchronized | ` Desynchronized WebGL2 canvas ` | limited | - | ✅ | ` safe ` | 1 | - |
| webgpu | ` WebGPU ` | limited | - | ✅ | ` safe `, ` typed ` | 258 | - |
| webgpu-subgroups | ` WebGPU subgroups ` | limited | - | ✅ | ` typed ` | 1 | - |
| webhid | ` WebHID ` | limited | - | ✅ | ` safe `, ` typed ` | 31 | - |
| webnn | ` WebNN ` | limited | - | ✅ | ` safe `, ` typed ` | 103 | - |
| webrtc | ` WebRTC ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 172 | - |
| webrtc-encoded-transform | ` WebRTC encoded transform ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 22 | - |
| webrtc-sctp | ` WebRTC SCTP information ` | widely | 2023 | ✅ | ` safe `, ` typed ` | 7 | - |
| webrtc-stats | ` WebRTC statistics ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 26 | - |
| websockets | ` WebSockets ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 25 | - |
| webtransport | ` WebTransport ` | newly | 2026 | ✅ | ` safe `, ` typed ` | 35 | - |
| webusb | ` WebUSB ` | limited | - | ✅ | ` safe `, ` typed ` | 104 | - |
| webvr | ` WebVR ` | limited | - | ✅ | ` safe `, ` typed ` | 73 | - |
| webvtt | ` WebVTT ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 4 | - |
| webvtt-cue-alignment | ` WebVTT cue alignment ` | limited | - | ✅ | ` typed ` | 2 | - |
| webvtt-cue-settings | ` WebVTT cue settings ` | widely | 2020 | ✅ | ` typed ` | 6 | - |
| webvtt-regions | ` WebVTT regions ` | limited | - | ✅ | ` safe `, ` typed ` | 11 | - |
| webxr-anchors | ` Anchors (WebXR) ` | limited | - | ✅ | ` safe `, ` typed ` | 14 | - |
| webxr-ar | ` Augmented reality ` | limited | - | ✅ | ` typed ` | 3 | - |
| webxr-camera | ` Raw camera access for WebXR ` | limited | - | ✅ | ` safe `, ` typed ` | 5 | - |
| webxr-depth-sensing | ` Depth sensing ` | limited | - | ✅ | ` safe `, ` typed ` | 14 | - |
| webxr-device | ` WebXR ` | limited | - | ✅ | ` safe `, ` typed ` | 105 | - |
| webxr-dom-overlays | ` DOM overlays for WebXR ` | limited | - | ✅ | ` typed ` | 2 | - |
| webxr-gamepads | ` Gamepad (WebXR) ` | limited | - | ✅ | ` typed ` | 1 | - |
| webxr-hand-input | ` Hand input ` | limited | - | ✅ | ` safe `, ` typed ` | 16 | - |
| webxr-hit-test | ` Hit test ` | limited | - | ✅ | ` safe `, ` typed ` | 18 | - |
| webxr-layers | ` Layers (WebXR) ` | limited | - | ✅ | ` safe `, ` typed ` | 64 | - |
| webxr-lighting-estimation | ` Lighting estimation ` | limited | - | ✅ | ` safe `, ` typed ` | 11 | - |
| wheel-events | ` Wheel events ` | limited | - | ✅ | ` safe `, ` typed ` | 8 | - |
| window | ` Window ` | widely | 2015 | ✅ | ` safe ` | 34 | - |
| window-controls-overlay | ` Window Controls Overlay ` | limited | - | ✅ | ` safe `, ` typed ` | 9 | - |
| window-management | ` Window management ` | limited | - | ✅ | ` safe `, ` typed ` | 18 | - |
| writingsuggestions | ` writingsuggestions ` | limited | - | ✅ | ` typed ` | 1 | - |
| xhr | ` XMLHttpRequest ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 59 | - |
| xml-serializer | ` XMLSerializer ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 3 | - |
| xpath | ` XPath ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 18 | - |

## JavaScript Builtins (javascript.*)

- total: `101`
- excluded (out-of-scope): `9`
- included (in-scope): `92`
- mapped: `92`
- coverage: `100.0%`

| Feature ID | Name | Baseline | Year | Mapped | Patterns | Descriptors | Memo |
| --- | --- | --- | --- | --- | --- | --- | --- |
| accessor-methods | ` Accessor methods ` | limited | - | ✅ | - | 0 | - |
| array | ` Array (initial support) ` | widely | 2015 | ✅ | ` typed ` | 11 | - |
| array-at | ` Array at() ` | widely | 2022 | ✅ | ` typed ` | 1 | - |
| array-by-copy | ` Array by copy ` | widely | 2023 | ✅ | ` typed ` | 4 | - |
| array-copywithin | ` Array copyWithin() ` | widely | 2016 | ✅ | ` typed ` | 1 | - |
| array-fill | ` Array fill() ` | widely | 2016 | ✅ | ` typed ` | 1 | - |
| array-find | ` Array find() and findIndex() ` | widely | 2016 | ✅ | ` typed ` | 2 | - |
| array-findlast | ` Array findLast() and findLastIndex() ` | widely | 2022 | ✅ | ` typed ` | 2 | - |
| array-flat | ` Array flat() and flatMap() ` | widely | 2020 | ✅ | ` typed ` | 2 | - |
| array-from | ` Array.from() ` | widely | 2016 | ✅ | ` safe ` | 1 | - |
| array-fromasync | ` Array.fromAsync() ` | newly | 2024 | ✅ | ` safe ` | 1 | - |
| array-group | ` Array grouping ` | newly | 2024 | ✅ | ` safe ` | 2 | - |
| array-includes | ` Array includes() ` | widely | 2016 | ✅ | ` typed ` | 1 | - |
| array-isarray | ` Array.isArray() ` | widely | 2015 | ✅ | ` safe ` | 1 | - |
| array-iteration-methods | ` Array iteration methods ` | widely | 2015 | ✅ | ` typed ` | 9 | - |
| array-iterators | ` Array iterators ` | widely | 2018 | ✅ | ` typed ` | 3 | - |
| array-of | ` Array.of() ` | widely | 2016 | ✅ | ` safe ` | 1 | - |
| array-splice | ` Array splice() ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| async-await | ` Async functions ` | widely | 2017 | ✅ | - | 0 | Covered by JS Language (syntax); |
| async-generators | ` Async generators ` | widely | 2020 | ✅ | ` typed ` | 3 | Covered by JS Language (syntax); |
| async-iterators | ` Async iterators and the for await..of loop ` | widely | 2020 | ✅ | ` safe ` | 1 | Covered by JS Language (syntax); |
| atomics-pause | ` Atomics.pause() ` | newly | 2025 | ✅ | ` safe ` | 1 | - |
| atomics-wait-async | ` Atomics.waitAsync() ` | newly | 2025 | ✅ | ` safe ` | 1 | - |
| bigint | ` BigInt ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 4 | - |
| bigint64array | ` BigInt64Array ` | widely | 2021 | ✅ | ` typed ` | 4 | - |
| date | ` Date ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 43 | - |
| date-get-year-set-year | ` getYear() and setYear() ` | limited | - | ✅ | ` typed ` | 2 | - |
| date-to-gmt-string | ` toGMTString() ` | limited | - | ✅ | ` typed ` | 1 | - |
| error-cause | ` Error cause ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 3 | - |
| escape-unescape | ` escape() and unescape() ` | limited | - | ✅ | - | 0 | Covered by JS Language (syntax); |
| explicit-resource-management | ` Explicit resource management ` | limited | - | ✅ | ` safe `, ` typed ` | 19 | - |
| float16array | ` Float16Array ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 3 | - |
| functions | ` Functions ` | widely | 2015 | ✅ | ` typed ` | 6 | - |
| functions-caller-arguments | ` Function caller and arguments ` | limited | - | ✅ | ` typed ` | 2 | Covered by JS Language (syntax); |
| generators | ` Generators ` | widely | 2016 | ✅ | ` typed ` | 3 | - |
| getorinsert | ` Map getOrInsert() ` | newly | 2026 | ✅ | ` typed ` | 4 | - |
| globalthis | ` globalThis ` | widely | 2020 | ✅ | - | 0 | - |
| html-wrapper-methods | ` HTML wrapper methods ` | limited | - | ✅ | ` typed ` | 14 | - |
| intl | ` Intl ` | widely | 2017 | ✅ | ` safe `, ` typed ` | 15 | - |
| intl-display-names | ` Intl.DisplayNames ` | widely | 2021 | ✅ | ` safe ` | 1 | - |
| intl-duration-format | ` Intl.DurationFormat ` | newly | 2025 | ✅ | ` safe ` | 1 | - |
| intl-list-format | ` Intl.ListFormat ` | widely | 2021 | ✅ | ` safe ` | 1 | - |
| intl-locale | ` Intl.Locale ` | widely | 2020 | ✅ | ` safe ` | 1 | - |
| intl-locale-info | ` Intl.Locale info ` | limited | - | ✅ | ` typed ` | 7 | - |
| intl-plural-rules | ` Intl.PluralRules ` | widely | 2019 | ✅ | ` safe ` | 1 | - |
| intl-relative-time-format | ` Intl.RelativeTimeFormat ` | widely | 2020 | ✅ | ` safe ` | 1 | - |
| intl-segmenter | ` Intl.Segmenter ` | newly | 2024 | ✅ | ` safe ` | 1 | - |
| is-error | ` Error.isError() ` | limited | - | ✅ | ` safe ` | 1 | - |
| iterator-concat | ` Iterator.concat() ` | newly | 2026 | ✅ | ` safe ` | 1 | - |
| iterator-methods | ` Iterator methods ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 12 | - |
| iterators | ` Iterators and the for...of loop ` | widely | 2015 | ❌ | - | - | Meta feature |
| javascript | ` JavaScript (initial core language support) ` | widely | 2015 | ✅ | ` typed ` | 5 | - |
| json | ` JSON ` | widely | 2015 | ✅ | ` safe ` | 2 | - |
| json-raw | ` JSON source text access ` | newly | 2025 | ✅ | ` safe ` | 2 | - |
| map | ` Map (initial support) ` | widely | 2015 | ✅ | ` typed ` | 10 | - |
| math-sum-precise | ` Math.sumPrecise() ` | newly | 2026 | ✅ | - | 0 | - |
| number | ` Math and numbers ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 62 | - |
| object-hasown | ` Object.hasOwn() ` | widely | 2022 | ✅ | ` safe ` | 1 | - |
| object-object | ` Object ` | widely | 2015 | ✅ | ` safe ` | 27 | - |
| promise | ` Promise (initial support) ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 6 | - |
| promise-allsettled | ` Promise.allSettled() ` | widely | 2020 | ✅ | ` safe ` | 1 | - |
| promise-any | ` Promise.any() ` | widely | 2020 | ✅ | ` safe `, ` typed ` | 2 | - |
| promise-finally | ` Promise finally() ` | widely | 2018 | ✅ | ` typed ` | 1 | - |
| promise-try | ` Promise.try() ` | newly | 2025 | ✅ | ` safe ` | 1 | - |
| promise-withresolvers | ` Promise.withResolvers() ` | newly | 2024 | ✅ | ` safe ` | 1 | - |
| proto | ` __proto__ ` | limited | - | ✅ | - | 0 | - |
| proxy-reflect | ` Proxy and Reflect ` | widely | 2016 | ✅ | ` safe ` | 14 | - |
| regexp | ` Regular expressions ` | widely | 2015 | ✅ | ` typed ` | 14 | - |
| regexp-compile | ` RegExp compile() ` | limited | - | ✅ | ` typed ` | 1 | - |
| regexp-escape | ` RegExp.escape() ` | newly | 2025 | ✅ | ` safe ` | 1 | - |
| regexp-static-properties | ` RegExp static properties ` | limited | - | ✅ | ` safe ` | 5 | - |
| resizable-buffers | ` Resizable buffers ` | newly | 2024 | ✅ | ` safe `, ` typed ` | 8 | - |
| serializable-errors | ` Serializable errors ` | limited | - | ❌ | - | - | Structured clone semantics — not static-detectable |
| set | ` Set (initial support) ` | widely | 2015 | ✅ | ` typed ` | 9 | - |
| set-methods | ` Set methods ` | newly | 2024 | ✅ | ` typed ` | 7 | - |
| shared-memory | ` SharedArrayBuffer and Atomics ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 14 | - |
| stable-array-sort | ` Stable array sort ` | widely | 2020 | ❌ | - | - | Semantics not AST-detectable (stable behavior) |
| string-at | ` String at() ` | widely | 2022 | ✅ | ` typed ` | 1 | - |
| string-codepoint | ` String codePointAt() and fromCodePoint() ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 2 | - |
| string-includes | ` String includes() ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| string-matchall | ` String matchAll() ` | widely | 2020 | ✅ | ` typed ` | 1 | - |
| string-normalize | ` String normalize() ` | widely | 2016 | ✅ | ` typed ` | 1 | - |
| string-pad | ` String padStart() and padEnd() ` | widely | 2017 | ✅ | ` typed ` | 2 | - |
| string-raw | ` String raw() ` | widely | 2015 | ✅ | ` safe ` | 1 | - |
| string-repeat | ` String repeat() ` | widely | 2015 | ✅ | ` typed ` | 1 | - |
| string-replaceall | ` String replaceAll() ` | widely | 2020 | ✅ | ` typed ` | 1 | - |
| string-startsends-with | ` String startsWith() and endsWith() ` | widely | 2015 | ✅ | ` typed ` | 2 | - |
| string-trim-startend | ` String trimStart() and trimEnd() ` | widely | 2020 | ✅ | ` typed ` | 2 | - |
| string-wellformed | ` String isWellFormed() and toWellFormed() ` | widely | 2023 | ✅ | ` typed ` | 2 | - |
| strings | ` String (initial support) ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 18 | - |
| symbol | ` Symbol ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 14 | - |
| temporal | ` Temporal ` | limited | - | ✅ | ` safe `, ` typed ` | 10 | - |
| transferable-arraybuffer | ` Transferable ArrayBuffer ` | newly | 2024 | ✅ | ` typed ` | 3 | Transfer semantics — not static-detectable |
| typed-array-iteration-methods | ` Typed array iteration methods ` | widely | 2016 | ✅ | ` typed ` | 99 | - |
| typed-array-iterators | ` Typed array iterators ` | widely | 2016 | ✅ | ` typed ` | 33 | - |
| typed-arrays | ` Typed arrays (initial support) ` | widely | 2015 | ✅ | ` safe `, ` typed ` | 22 | - |
| uint8array-base64-hex | ` Uint8Array base64 and hex conversion ` | newly | 2025 | ✅ | ` safe `, ` typed ` | 6 | - |
| weak-references | ` Weak references ` | widely | 2021 | ✅ | ` safe `, ` typed ` | 5 | - |
| weakmap | ` WeakMap ` | widely | 2015 | ✅ | ` typed ` | 4 | - |
| weakset | ` WeakSet ` | widely | 2015 | ✅ | ` typed ` | 3 | - |
| with | ` with ` | limited | - | ✅ | ` safe ` | 1 | - |