Microsoft Edge 143 web platform release notes (Dec. 2025) (#3619)

captainbrosset · mikehoffms · undefined · web-flow · commit c8877e167db7 · 2025-11-03T11:36:16.000+01:00
* New web platform release notes for 143

* initial Writer/Editor pass

* re-outline

* date, and&gt;or

* improve headings

* Detailed contents

* esc link text

* 142 date

* linkfix

* no rum

* see also

* .

* Move some features which moved to 143

* Finalized edit pass

* toc

* sss

---------

Co-authored-by: captainbrosset &lt;captainbrosset@users.noreply.github.com&gt;
Co-authored-by: Michael Hoffman &lt;45407486+mikehoffms@users.noreply.github.com&gt;
Co-authored-by: undefined &lt;undefined@users.noreply.github.com&gt;
diff --git a/microsoft-edge/toc.yml b/microsoft-edge/toc.yml
@@ -30,6 +30,10 @@
           href: ./web-platform/release-notes/index.md
           displayName: what's new, announcements
 
+        - name: Microsoft Edge 143
+          href: ./web-platform/release-notes/143.md
+          displayName: Microsoft Edge 143 web platform release notes (Dec. 2025)  # page title
+
         - name: Microsoft Edge 142
           href: ./web-platform/release-notes/142.md
           displayName: Microsoft Edge 142 web platform release notes (Oct. 2025)  # page title
diff --git a/microsoft-edge/web-platform/release-notes/133.md b/microsoft-edge/web-platform/release-notes/133.md
@@ -40,7 +40,7 @@ To stay up-to-date and get the latest web platform features, download a preview
     * [WebGPU: 1-component vertex formats (and `unorm8x4-bgra`)](#webgpu-1-component-vertex-formats-and-unorm8x4-bgra)
     * [X25519 algorithm of the Web Cryptography API](#x25519-algorithm-of-the-web-cryptography-api)
     * [popover=hint](#popoverhint)
-  * [Deprecated and removed features](#deprecated-and-removed-features)
+  * [Deprecated or removed features](#deprecated-or-removed-features)
     * [Deprecate WebGPU limit maxInterStageShaderComponents](#deprecate-webgpu-limit-maxinterstageshadercomponents)
     * [Remove `<link rel=prefetch>` five-minute rule](#remove-link-relprefetch-five-minute-rule)
 * [Origin trials](#origin-trials)
@@ -64,7 +64,7 @@ See [What's New in DevTools (Microsoft Edge 133)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [1.0.3065.39](../../webview2/release-notes/archive.md#10306539) in _Archived Release Notes for the WebView2 SDK_ (Feb. 2025).
+See [1.0.3065.39](../../webview2/release-notes/archive.md#10306539) (Feb. 2025) in _Archived Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
@@ -275,7 +275,9 @@ The Popover API specifies the behavior for two values of the `popover` attribute
 
 
 <!-- ------------------------------ -->
-#### Deprecated and removed features
+#### Deprecated or removed features
+
+The following Web API features have been deprecated (still supported, but not recommended) or removed.
 
 
 <!-- ---------- -->
diff --git a/microsoft-edge/web-platform/release-notes/134.md b/microsoft-edge/web-platform/release-notes/134.md
@@ -52,7 +52,7 @@ See [What's New in DevTools (Microsoft Edge 134)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [1.0.3124.44](../../webview2/release-notes/archive.md#10312444) in _Release Notes for the WebView2 SDK_ (March 2025).
+See [1.0.3124.44](../../webview2/release-notes/archive.md#10312444) (March 2025) in _Archived Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
diff --git a/microsoft-edge/web-platform/release-notes/135.md b/microsoft-edge/web-platform/release-notes/135.md
@@ -46,7 +46,7 @@ To stay up-to-date and get the latest web platform features, download a preview
     * [Timestamps for RTC Encoded Frames](#timestamps-for-rtc-encoded-frames)
     * [fetchLater API](#fetchlater-api)
     * [highlightsFromPoint API](#highlightsfrompoint-api)
-  * [Deprecated and removed features](#deprecated-and-removed-features)
+  * [Deprecated or removed features](#deprecated-or-removed-features)
     * [Remove `navigator.xr.supportsSession` method](#remove-navigatorxrsupportssession-method)
     * [Remove WebGPU limit `maxInterStageShaderComponents`](#remove-webgpu-limit-maxinterstageshadercomponents)
 * [Origin trials](#origin-trials)
@@ -66,10 +66,7 @@ See [What's New in DevTools (Microsoft Edge 135)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [Release Notes for the WebView2 SDK](../../webview2/release-notes/index.md).
-<!-- todo: when exists in April 2025, use instead:
-For WebView2, see [1.0.n.n](../../webview2/release-notes/index.md#10nnnnnn) in _Release Notes for the WebView2 SDK_ (Apr. 2025).
--->
+See [1.0.3179.45](../../webview2/release-notes/archive.md#10317945 ) (Apr. 2025) in _Archived Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
@@ -319,7 +316,9 @@ Getting highlights from a point can be used by a web app to manage user interact
 
 
 <!-- ------------------------------ -->
-#### Deprecated and removed features
+#### Deprecated or removed features
+
+The following Web API features have been deprecated (still supported, but not recommended) or removed.
 
 
 <!-- ---------- -->
diff --git a/microsoft-edge/web-platform/release-notes/136.md b/microsoft-edge/web-platform/release-notes/136.md
@@ -43,9 +43,8 @@ To stay up-to-date and get the latest web platform features, download a preview
     * [Web Authentication Conditional Create](#web-authentication-conditional-create)
     * [Return multiple identity providers in a single FedCM `get()` call](#return-multiple-identity-providers-in-a-single-fedcm-get-call)
     * [`RegExp.escape()`](#regexpescape)
-  * [Deprecated and removed features](#deprecated-and-removed-features)
+  * [Deprecated or removed features](#deprecated-or-removed-features)
     * [Deprecate the `AutomaticHttpsDefault` policy](#deprecate-the-automatichttpsdefault-policy)
-    * [Deprecate `Intl.Locale` getters](#deprecate-intllocale-getters)
 * [Origin trials](#origin-trials)
   * [New Chromium origin trials](#new-chromium-origin-trials)
     * [Update of Canvas text rendering implementation](#update-of-canvas-text-rendering-implementation)
@@ -65,7 +64,7 @@ See [What's New in DevTools (Microsoft Edge 136)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [1.0.3240.44](../../webview2/release-notes/index.md#10324044) in _Release Notes for the WebView2 SDK_ (May 2025).
+See [1.0.3240.44](../../webview2/release-notes/index.md#10324044) (May 2025) in _Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
@@ -313,7 +312,9 @@ See [RegExp.escape()](https://developer.mozilla.org/docs/Web/JavaScript/Referenc
 
 
 <!-- ------------------------------ -->
-#### Deprecated and removed features
+#### Deprecated or removed features
+
+The following Web API features have been deprecated (still supported, but not recommended) or removed.
 
 
 <!-- ---------- -->
@@ -322,16 +323,6 @@ See [RegExp.escape()](https://developer.mozilla.org/docs/Web/JavaScript/Referenc
 The `AutomaticHttpsDefault` policy is supported but discouraged in Microsoft Edge 136, and is planned to be removed in Microsoft Edge 139.  Instead, use the new `HttpsUpgradesEnabled`<!-- todo: add link to the new policy on https://learn.microsoft.com/en-us/deployedge/microsoft-edge-update-policies when available --> policy, which is available starting in Microsoft Edge version 136.
 
 
-<!-- ---------- -->
-###### Deprecate `Intl.Locale` getters
-
-The `Intl.Locale` API exposes information for a locale, including its week elements and its hour cycle type, such as 12-hour clock, Japanese 12-hour clock, or 24-hour clock.
-
-The accessor properties of the `Intl.Locale` object are now deprecated, in favor of the corresponding functions, per the specification.  For example, the `Intl.Locale.prototype.hourCycle` accessor property is deprecated in favor of the `Intl.Locale.prototype.getHourCycles()` function.
-
-See [Intl.Locale](https://developer.mozilla.org/docs/Web/JavaScript/Reference/Global_Objects/Intl/Locale) at MDN.
-
-
 <!-- ====================================================================== -->
 ## Origin trials
 
diff --git a/microsoft-edge/web-platform/release-notes/137.md b/microsoft-edge/web-platform/release-notes/137.md
@@ -59,7 +59,7 @@ See [What's New in DevTools (Microsoft Edge 137)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [1.0.3296.44](../../webview2/release-notes/index.md#10329644) in _Release Notes for the WebView2 SDK_ (June 2025).
+See [1.0.3296.44](../../webview2/release-notes/index.md#10329644) (June 2025) in _Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
diff --git a/microsoft-edge/web-platform/release-notes/138.md b/microsoft-edge/web-platform/release-notes/138.md
@@ -57,7 +57,7 @@ See [What's New in DevTools (Microsoft Edge 138)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [1.0.3296.44](../../webview2/release-notes/index.md#10329644) in _Release Notes for the WebView2 SDK_ (June 2025).
+See [1.0.3296.44](../../webview2/release-notes/index.md#10329644) (June 2025) in _Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
diff --git a/microsoft-edge/web-platform/release-notes/139.md b/microsoft-edge/web-platform/release-notes/139.md
@@ -25,7 +25,6 @@ To stay up-to-date and get the latest web platform features, download a preview
     * [CSS `corner-shape` property](#css-corner-shape-property)
   * [Web APIs](#web-apis)
     * [`request-close` invoker command](#request-close-invoker-command)
-    * [Allow more characters in JavaScript DOM APIs](#allow-more-characters-in-javascript-dom-apis)
     * [Audio level for WebRTC encoded frames](#audio-level-for-webrtc-encoded-frames)
     * [Specify a crash-reporting endpoint to receive only crash reports](#specify-a-crash-reporting-endpoint-to-receive-only-crash-reports)
     * [Fire error event instead of throwing for CSP blocked worker](#fire-error-event-instead-of-throwing-for-csp-blocked-worker)
@@ -62,7 +61,7 @@ See [What's New in DevTools (Microsoft Edge 139)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [1.0.3405.78](../../webview2/release-notes/index.md#10340578) in _Release Notes for the WebView2 SDK_ (Aug 2025).
+See [1.0.3405.78](../../webview2/release-notes/index.md#10340578) (Aug. 2025) in _Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
@@ -141,17 +140,6 @@ See also:
 * [Invoker Commands API](https://developer.mozilla.org/docs/Web/API/Invoker_Commands_API) at MDN.
 
 
-<!-- ---------- -->
-###### Allow more characters in JavaScript DOM APIs
-
-You can now create DOM elements and attributes with a wider variety of valid characters in JavaScript. This matches the behavior for when the same elements and attributes are defined in HTML markup.
-
-This change aligns the JavaScript DOM APIs with the HTML parser, which allows a broader set of characters for element names and attributes.
-
-See also:
-* [Allow more characters in javascript DOM APIs](https://chromestatus.com/feature/6278918763708416)
-
-
 <!-- ---------- -->
 ###### Audio level for WebRTC encoded frames
 
diff --git a/microsoft-edge/web-platform/release-notes/140.md b/microsoft-edge/web-platform/release-notes/140.md
@@ -56,7 +56,7 @@ See [What's New in DevTools (Microsoft Edge 140)](../../devtools/whats-new/2025/
 <!-- ====================================================================== -->
 ## WebView2
 
-See [1.0.3485.44](../../webview2/release-notes/index.md#10348544) in _Release Notes for the WebView2 SDK_ (Sep. 2025).
+See [1.0.3485.44](../../webview2/release-notes/index.md#10348544) (Sep. 2025) in _Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
diff --git a/microsoft-edge/web-platform/release-notes/141.md b/microsoft-edge/web-platform/release-notes/141.md
@@ -44,19 +44,13 @@ To stay up-to-date and get the latest web platform features, download a preview
 <!-- ====================================================================== -->
 ## Edge DevTools
 
-See [What's New in Microsoft Edge DevTools](../../devtools/whats-new/whats-new.md).
-<!-- todo: when it exists in Oct 2025, use instead:
 See [What's New in DevTools (Microsoft Edge 141)](../../devtools/whats-new/2025/10/devtools-141.md).
--->
 
 
 <!-- ====================================================================== -->
 ## WebView2
 
-See [Release Notes for the WebView2 SDK](../../webview2/release-notes/index.md).
-<!-- todo: when exists in Oct 2025, use instead:
-See [1.0.n.n](../../webview2/release-notes/index.md#10nnnnnn) in _Release Notes for the WebView2 SDK_ (Oct 2025).
--->
+See [1.0.3537.50](../../webview2/release-notes/index.md#10353750) (Oct. 2025) in _Release Notes for the WebView2 SDK_.
 
 
 <!-- ====================================================================== -->
diff --git a/microsoft-edge/web-platform/release-notes/142.md b/microsoft-edge/web-platform/release-notes/142.md
@@ -5,12 +5,9 @@ author: MSEdgeTeam
 ms.author: msedgedevrel
 ms.topic: conceptual
 ms.service: microsoft-edge
-ms.date: 10/19/2025
+ms.date: 10/30/2025
 ---
 # Microsoft Edge 142 web platform release notes (Oct. 2025)
-<!-- todo: after Sep. 30, 2025, change date: yaml field to:
-ms.date: 10/30/2025
--->
 
 The following are the new web platform features and updates in Microsoft Edge 142, which releases on October 30, 2025.
 
@@ -22,21 +19,17 @@ To stay up-to-date and get the latest web platform features, download a preview
 * [WebView2](#webview2)
 * [CSS features](#css-features)
    * [AccentColor and AccentColorText system colors](#accentcolor-and-accentcolortext-system-colors)
-   * [CSS font-language-override property](#css-font-language-override-property)
    * [document.activeViewTransition property](#documentactiveviewtransition-property)
    * [Range syntax for style container queries and if() functions](#range-syntax-for-style-container-queries-and-if-functions)
 * [SVG features](#svg-features)
    * [Support download attribute in SVG \<a\> element](#support-download-attribute-in-svg-a-element)
    * [CSS width and height support for SVG \<use\> element](#css-width-and-height-support-for-svg-use-element)
 * [Web APIs](#web-apis)
    * [Clear the window.name value for cross-site navigations that switch browsing context group](#clear-the-windowname-value-for-cross-site-navigations-that-switch-browsing-context-group)
-   * [clipboardchange event](#clipboardchange-event)
-   * [dataTransfer property for insertFromPaste, insertFromDrop, and insertReplacementText input events](#datatransfer-property-for-insertfrompaste-insertfromdrop-and-insertreplacementtext-input-events)
    * [Show third-party iframe origins in the FedCM UI](#show-third-party-iframe-origins-in-the-fedcm-ui)
    * [HSTS tracking prevention](#hsts-tracking-prevention)
    * [Only fire pointerrawupdate events in secure contexts](#only-fire-pointerrawupdate-events-in-secure-contexts)
    * [Enable sticky user activation across same-origin navigations](#enable-sticky-user-activation-across-same-origin-navigations)
-   * [New PWA manifest update algorithm](#new-pwa-manifest-update-algorithm)
    * [Web Speech API contextual biasing](#web-speech-api-contextual-biasing)
 * [Origin trials in Microsoft Edge](#origin-trials-in-microsoft-edge)
    * [AriaNotify API](#arianotify-api)
@@ -55,7 +48,7 @@ To stay up-to-date and get the latest web platform features, download a preview
 ## Edge DevTools
 
 See [What's New in Microsoft Edge DevTools](../../devtools/whats-new/whats-new.md).
-<!-- todo: when it exists in Oct 2025, use instead:
+<!-- todo: when it exists in Oct/Nov 2025, use instead:
 See [What's New in DevTools (Microsoft Edge 142)](../../devtools/whats-new/2025/10/devtools-142.md).
 -->
 
@@ -64,8 +57,8 @@ See [What's New in DevTools (Microsoft Edge 142)](../../devtools/whats-new/2025/
 ## WebView2
 
 See [Release Notes for the WebView2 SDK](../../webview2/release-notes/index.md).
-<!-- todo: when exists in Oct 2025, use instead:
-For WebView2, see [1.0.n.n](../../webview2/release-notes/index.md#10nnnnnn) in _Release Notes for the WebView2 SDK_ (Oct 2025).
+<!-- todo: when exists in Oct/Nov 2025, use instead:
+For WebView2, see [1.0.n.n](../../webview2/release-notes/index.md#10nnnnnn) (Oct./Nov. 2025) in _Release Notes for the WebView2 SDK_.
 -->
 
 
@@ -85,17 +78,6 @@ See also:
 * [system Colors](https://drafts.csswg.org/css-color/#css-system-colors) in _CSS Color Module Level 4_.
 
 
-<!-- ------------------------------ -->
-#### CSS `font-language-override` property
-
-The `font-language-override` CSS property allows you to override the system language used for OpenType glyph substitution, by specifying a four-character language tag directly in CSS.
-
-This enables finer-grained typographic control for multilingual content, or for fonts with language-specific glyph variants.
-
-See also:
-* [font-language-override](https://developer.mozilla.org/docs/Web/CSS/font-language-override) at MDN.
-
-
 <!-- ------------------------------ -->
 #### `document.activeViewTransition` property
 
@@ -229,33 +211,6 @@ See also:
 * [Browsing context](https://developer.mozilla.org/docs/Glossary/Browsing_context) at MDN.
 
 
-<!-- ------------------------------ -->
-#### `clipboardchange` event
-
-The Clipboard API now fires a `clipboardchange` event whenever the content of the system clipboard changes.
-
-The `clipboardchange` event provides an efficient alternative to polling techniques, such as using JavaScript to read the clipboard content at regular intervals of time.
-
-See also:
-* [Clipboard API](https://developer.mozilla.org/docs/Web/API/Clipboard_API) at MDN.
-
-
-<!-- ------------------------------ -->
-#### `dataTransfer` property for `insertFromPaste`, `insertFromDrop`, and `insertReplacementText` input events
-
-The input event objects of type `insertFromPaste`, `insertFromDrop`, and `insertReplacementText` now have a `dataTransfer` property, for better interoperability with other browsers.
-
-The `dataTransfer` property provides access to the clipboard or drag-and-drop data when the user edits text within a `contenteditable` element.  The same data is also available on the `dataTransfer` property of `beforeinput` events.
-
-This feature only applies to `contenteditable` elements.
-
-See also:
-* [DataTransfer](https://developer.mozilla.org/docs/Web/API/DataTransfer) at MDN.
-* [InputEvent: inputType property](https://developer.mozilla.org/docs/Web/API/InputEvent/inputType) at MDN.
-* [HTML contenteditable global attribute](https://developer.mozilla.org/docs/Web/HTML/Reference/Global_attributes/contenteditable) at MDN.
-* [Element: beforeinput event](https://developer.mozilla.org/docs/Web/API/Element/beforeinput_event) at MDN.
-
-
 <!-- ------------------------------ -->
 #### Show third-party iframe origins in the FedCM UI
 
@@ -301,27 +256,6 @@ See also:
 * [Sticky activation](https://developer.mozilla.org/docs/Glossary/Sticky_activation) at MDN.
 
 
-<!-- ------------------------------ -->
-#### New PWA manifest update algorithm
-
-The updating of installed PWAs uses a new algorithm.  The new update algorithm makes the update process more deterministic and predictable, and gives you more control over whether, and when, updates should apply to existing installations of your app.
-
-The new update algorithm has the following benefits:
-
-* **Consistency:** The algorithm provides a consistent way to detect when a manifest update should happen.
-
-* **Reduced user interruptions:** App users won't see the update dialog, except when it's strictly necessary, such as to confirm security-sensitive changes.
-
-* **Browser flexibility:** Microsoft Edge can now allow known, trusted apps to update without displaying a notification, and can block updates for known bad apps.
-
-* **Developer control:** You have more control over when the update dialog is shown to users.
-
-* **Reduce network traffic:** Unnecessary network traffic is minimized.
-
-See also:
-* [Predictable Web App Updating - Explainer](https://github.com/WICG/manifest-incubations/blob/gh-pages/predictable-app-updating.md)
-
-
 <!-- ------------------------------ -->
 #### Web Speech API contextual biasing
 
diff --git a/microsoft-edge/web-platform/release-notes/143.md b/microsoft-edge/web-platform/release-notes/143.md
diff --git a/microsoft-edge/web-platform/site-impacting-changes.md b/microsoft-edge/web-platform/site-impacting-changes.md
