<!--
{
  "documentType" : "article",
  "framework" : "Safari Technology Preview Release Notes",
  "identifier" : "/documentation/Safari-Technology-Preview-Release-Notes/stp-release-213",
  "metadataVersion" : "0.1.0",
  "role" : "article",
  "title" : "Safari Technology Preview 213 Release Notes"
}
-->

# Safari Technology Preview 213 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: CSS, Editing, Forms, HTML, JavaScript, Media, Networking, PDF, Rendering, Storage, SVG, Tables, Text, Web Animations, Web API, Web Extensions, Web Inspector, and WebRTC.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 213 is now [available for download](https://developer.apple.com/safari/resources/) for macOS Sequoia and macOS Sonoma. If you already have Safari Technology Preview installed, you can update it in System Settings under General → Software Update.

This release includes WebKit changes between: [288458@main…289651@main](https://github.com/WebKit/WebKit/compare/1e3a17caec13822eb8f0cc09a21038b31ba233b2...a37e58d21cec250a340faaf8995c428587e2b15f).

### CSS

#### New Features

- Implemented `unicode-bidi` text rendering UA rules (except for `ruby` elements). ([288511@main](https://commits.webkit.org/288511@main))  (142191490)
- Added support for gradients with only one stop. ([289469@main](https://commits.webkit.org/289469@main))  (142796999)

#### Resolved Issues

- Fixed `contain: size` breaking `object-fit`. ([289287@main](https://commits.webkit.org/289287@main))  (131866042)
- Fixed broken `revert-layer` when logical group CSS properties are explicitly inherited. ([289183@main](https://commits.webkit.org/289183@main))  (140819138)
- Fixed subsequent nested styles getting ignored after an incorrect nested selector. ([289429@main](https://commits.webkit.org/289429@main))  (142187930)
- Fixed `font-variant-caps: all-small-caps` causing incorrect `box-sizing` in `flex` inline context. ([289486@main](https://commits.webkit.org/289486@main))  (142212550)
- Fixed ensuring  the correct logic is run for over-constrained cases when the absolute positioned box is a `writing-mode` root. ([288797@main](https://commits.webkit.org/288797@main))  (142214631)
- Fixed `text-box-trim` accumulation failing when updating the CSS dynamically. ([288480@main](https://commits.webkit.org/288480@main))  (142386761)
- Fixed `text-emphasis` to not paint emphasis marks on punctuations. ([288476@main](https://commits.webkit.org/288476@main))  (142387538)
- Fixed sizing and positioning issues when a popover changes CSS position upon opening. ([288655@main](https://commits.webkit.org/288655@main))  (142491219)
- Fixed view transitions to stop running when the user navigates with a swipe. ([288956@main](https://commits.webkit.org/288956@main))  (142844150)

### Editing

#### Resolved Issues

- Fixed `document.execCommand("copy")` only triggering if there is a selection. ([288559@main](https://commits.webkit.org/288559@main))  (27792460)
- Fixed Hebrew text pasted from Safari getting aligned left. ([289323@main](https://commits.webkit.org/289323@main))  (139029945)
- Fixed setting selection to not set focus unless there is an existing selection. ([288555@main](https://commits.webkit.org/288555@main))  (139075809)

### Forms

#### Resolved Issues

- Fixed `<datalist>` dropdown keyboard interactions to align with platform conventions. ([289067@main](https://commits.webkit.org/289067@main))  (143012287)
- Fixed: Disabled all Writing Tools app menu items, except “Compose”, for empty editable content. ([289243@main](https://commits.webkit.org/289243@main))  (143332082)

### HTML

#### Deprecations

- Removed the `composite` attribute on an `<img>` element. ([289071@main](https://commits.webkit.org/289071@main))  (143109250)

### JavaScript

#### Resolved Issues

- Fixed: Increased the `matchLimit` for regular expressions, allowing complex matches on longer strings. ([289319@main](https://commits.webkit.org/289319@main))  (143202375)

### Media

#### New Features

- Enabled MediaSource prefers DecompressionSession by default. ([289924@main](https://commits.webkit.org/289924@main))  (142761051)
- Enabled WebCodec’s AudioEncoder and AudioDecoder by default. ([288965@main](https://commits.webkit.org/288965@main))  (142916087)

#### Resolved Issues

- Fixed handling an empty `srcAttr` in Media Element. ([289432@main](https://commits.webkit.org/289432@main))  (132042925)
- Fixed the `space` key not pausing a video in fullscreen by making the video mouse focusable. ([289220@main](https://commits.webkit.org/289220@main))  (138037616)
- Fixed playing video generating non-monotonic ‘timeupdate’ events. ([288722@main](https://commits.webkit.org/288722@main))  (142275184) (FB16222910)
- Fixed websites calling `play()` during a `seek()` is allowed by the specification so that the play event is fired even if the seek hasn’t completed. ([288577@main](https://commits.webkit.org/288577@main))  (142517488)
- Fixed seek not completing for WebM under some circumstances.  (143372794)
- Fixed MediaRecorderPrivateEncoder writing frames out of order. ([289643@main](https://commits.webkit.org/289643@main))  (143956063)

### Networking

#### Deprecations

- Changed 3DES cipher to show a warning to users that it is a legacy TLS cipher. ([288742@main](https://commits.webkit.org/288742@main))  (138948491)

### PDF

#### Resolved Issues

- Fixed switching a PDF from continuous to discrete mode displaying the page(s) that are at the top of the window, even when barely visible. ([289212@main](https://commits.webkit.org/289212@main))  (137608841)
- Fixed the “Previous Page” context menu option not navigating to previous page in 2-up continuous mode. ([289337@main](https://commits.webkit.org/289337@main))  (139817364)

### Rendering

#### Resolved Issues

- Fixed adding out-of-flow objects under the inline in a continuation chain, when possible. ([289451@main](https://commits.webkit.org/289451@main))  (102421379)
- Fixed the missing table collapsed border for `<thead>`, `<tbody>`, and `<tfoot>` elements in the wrong order. ([289434@main](https://commits.webkit.org/289434@main))  (110430887)
- Fixed `<input type="range">` taking up space even with `width: 0` applied. ([289184@main](https://commits.webkit.org/289184@main))  (113402515)
- Fixed absolute positioned child with percent to include containing block padding. ([288460@main](https://commits.webkit.org/288460@main))  (142321535)
- Fixed a border not showing when a linear gradient and a border radius are set. ([289101@main](https://commits.webkit.org/289101@main))  (142617573)
- Fixed relative-positioned input elements in scroll areas not rendering outlines. ([289154@main](https://commits.webkit.org/289154@main))  (142995142)
- Fixed tabbing out of a popover causing a hang in certain cases. ([289277@main](https://commits.webkit.org/289277@main))  (143145544)

### Storage

#### Resolved Issues

- Fixed the Storage Access API to consider `AllExceptPartitioned` as not currently having cookie access, ensuring sites can request access to first-party cookie. ([289450@main](https://commits.webkit.org/289450@main))  (143508260)

### SVG

#### New Features

- Added support for the `ch` length type for character width, but does not include support for upright vertical character width. ([288558@main](https://commits.webkit.org/288558@main))  (142463263)

#### Resolved Issues

- Fixed not propagating bbox for empty `text` to ancestors. ([289394@main](https://commits.webkit.org/289394@main))  (115217040)
- Fixed dynamically updating the `transform` attribute. ([289022@main](https://commits.webkit.org/289022@main))  (140761655)
- Fixed `SVGElement.prototype.ownerSVGElement` on the outermost `<svg>` in `foreignObject`. ([289388@main](https://commits.webkit.org/289388@main))  (143625675)

### Tables

#### Resolved Issues

- Fixed missing behavior for `rowspan="0"` on HTML tables where 0 means span over all the remaining rows. ([288746@main](https://commits.webkit.org/288746@main))  (133910430)
- Fixed table section and row background to not be treated as opaque. ([289047@main](https://commits.webkit.org/289047@main))  (142588505)

### Text

#### Resolved Issues

- Fixed displaying OpenType-SVG color fonts. ([288980@main](https://commits.webkit.org/288980@main))  (137496217) (FB15426148)

### Web Animations

#### Resolved Issues

- Fixed computing the time offset as needed when applying accelerated actions. ([288652@main](https://commits.webkit.org/288652@main))  (142604875)

### Web API

#### New Features

- Added support for the URLPattern API. ([288942@main](https://commits.webkit.org/288942@main))  (142967833)

#### Resolved Issues

- Fixed: Aligned some MIME type handling in EME with the MIME Sniffing standard. ([288916@main](https://commits.webkit.org/288916@main))  (114311586)
- Fixed: Updated `selectorText` handling to align with the specification for CSSPageRule. ([289428@main](https://commits.webkit.org/289428@main))  (125588212)
- Fixed matching emoji in an element’s `id` attribute from a `<link rel=expect>` with an `href` that uses percent-encoded syntax. ([289174@main](https://commits.webkit.org/289174@main))  (134531921)
- Fixed render blocking for `<link>` to not match elements that are on a ‘stack of open elements’ for the parser. ([289020@main](https://commits.webkit.org/289020@main))  (135846827)
- Fixed Distraction Control unexpectedly hiding out-of-flow elements that overlap with a hidden element. ([288593@main](https://commits.webkit.org/288593@main))  (136358918)
- Fixed the HTML parser phone number handling to better account for MathML. ([288706@main](https://commits.webkit.org/288706@main))  (141632782)

#### Deprecations

- Removed wheel event handling for `<input type="number">` to match platform conventions. ([289285@main](https://commits.webkit.org/289285@main))  (99318505)

### Web Extensions

#### Resolved Issues

- Fixed the `tabs` field missing from the result returned by `windows.create`. ([288949@main](https://commits.webkit.org/288949@main))  (138529797)
- Fixed the `webRequest.onBeforeRequest` event missing the `requestBody`. ([288813@main](https://commits.webkit.org/288813@main))  (140338580) (FB15911234)
- Fixed blurry extension icons. ([288529@main](https://commits.webkit.org/288529@main))  (142070967) (FB16171862)
- Fixed not picking the “zh” locale when “zh-Hant” is preferred. ([288974@main](https://commits.webkit.org/288974@main))  (142602243) (FB16271745)
- Fixed `webRequest` event listeners to honor `extraInfoSpec` for better performace. ([288938@main](https://commits.webkit.org/288938@main))  (142907168)
- Fixed web extension resources to be treated as UTF-8 by default. ([289086@main](https://commits.webkit.org/289086@main))  (143079179)

### Web Inspector

#### Resolved Issues

- Fixed style rules to stay editable after being modified by CSSOM in JavaScript. ([288948@main](https://commits.webkit.org/288948@main))  (124650808)

### WebRTC

#### Resolved Issues

- Fixed switching from speaker to receiver does not work the first time, but only the second time. ([289006@main](https://commits.webkit.org/289006@main))  (141685006)

---

Copyright &copy; 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)