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# Safari Technology Preview 189 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: CSS, HTML, JavaScript, Rendering, SVG, Web API, Web Inspector, WebAuthn, WebGL, and WebRTC.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 189 is now [available for download](https://developer.apple.com/safari/resources/) for macOS Sonoma and macOS Ventura. 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: [273602@main…274066@main](https://github.com/WebKit/WebKit/compare/b96b33ee6c4c6dde7bf51c3744d6ccbc19a517e8...6b46c24db81426c056f4f1f6fe915c2cdd687a1e).

### CSS

#### New Features

- Added support for `light-dark()` function for color values. ([273634@main](https://commits.webkit.org/273634@main))  (117033939)
- Added support for `@starting-style`. ([273740@main](https://commits.webkit.org/273740@main))  (121918611)

#### Resolved Issues

- Fixed named at-rule container getting skipped when  the container is named in a `:host` selector. ([273987@main](https://commits.webkit.org/273987@main))  (120428386)
- Fixed the name for a `::slotted` pseudo-element in a container query getting resolved against the wrong scope. ([274050@main](https://commits.webkit.org/274050@main))  (122224135)

#### Deprecations

- Removed `:-webkit-full-screen-ancestor` pseudo-class. ([273620@main](https://commits.webkit.org/273620@main))  (100782937)
- Removed `:-webkit-full-screen-controls-hidden` pseudo-class. ([273619@main](https://commits.webkit.org/273619@main))  (121323330)
- Removed `:-webkit-full-page-media` pseudo-class. ([273618@main](https://commits.webkit.org/273618@main))  (121752962)
- Removed `:-webkit-full-screen-document` pseudo-class. ([273639@main](https://commits.webkit.org/273639@main))  (121816310)

### HTML

#### Resolved Issues

- Fixed “about:blank” `document.referrer` initialization. ([278830@main](https://commits.webkit.org/278830@main))  (97689906)
- Fixed parsing a self-closing SVG script element. It now successfully executes. ([273697@main](https://commits.webkit.org/273697@main))  (121887875)

### JavaScript

#### Resolved Issues

- Fixed throwing a `RangeError` if `Set` methods are called on an object with negative `size` property. ([274009@main](https://commits.webkit.org/274009@main))  (121310940)
- Fixed `eval()` function from another realm to not cause a direct `eval` call. ([273782@main](https://commits.webkit.org/273782@main))  (121546048)
- Fixed `eval()` call with `...spread` syntaxt to be a direct call. ([273788@main](https://commits.webkit.org/273788@main))  (121547890)
- Fixed programming style for bitwise and in setExpectionPorts. ([273960@main](https://commits.webkit.org/273960@main))  (122138733)

### Rendering

#### Resolved Issues

- Fixed Greek uppercase transforms failing for some characters. ([274036@main](https://commits.webkit.org/274036@main))  (90364897)
- Fixed lingering boxes with `content-visibility: hidden`.  (117916396)
- Fixed: FIXME: Fixed graphics artifacts when scrolling a Heroku app. ([273999@main](https://commits.webkit.org/273999@main))  (120373474)
- Fixed `align-content` and `justify-content` on scroll containers causing overflowing content to become inaccessible. ([273737@main](https://commits.webkit.org/273737@main))  (121366949)
- Fixed a line break at gaps between two inline elements in a container with `white-space: nowrap`.  (121859917)
- Fixed a floating element causing the latter half of a hyphenated word to disappear. ([273836@main](https://commits.webkit.org/273836@main))  (121889487)
- Fixed cropped first letter for custom fonts that report negative advance width.  (121891210)

### SVG

#### Resolved Issues

- Fixed SVG title to have `display: none` as the default UA style rule. ([273991@main](https://commits.webkit.org/273991@main))  (122185838)

### Web API

#### Resolved Issues

- Fixed `history.pushState()` and `history.replaceState()` to ignore the `title` argument. ([273650@main](https://commits.webkit.org/273650@main))  (75695791)
- Fixed `lang` attribute in no namespace to only apply to HTML and SVG elements. ([273726@main](https://commits.webkit.org/273726@main))  (117795695)
- Fixed the spelling of `clonable`. ([274063@main](https://commits.webkit.org/274063@main))  (121516711)

#### Deprecations

- Removed `which` from `KeyboardEvent`. ([273701@main](https://commits.webkit.org/273701@main))  (106580687)

### Web Inspector

#### New Features

- Added a Media details panel to Web Inspector when selecting a `<video>` or `<audio>` element in the Elements tab. ([273777@main](https://commits.webkit.org/273777@main))  (118865793)

#### Resolved Issues

- Fixed font sizes in the Audits tab. ([273615@main](https://commits.webkit.org/273615@main))  (76162927)

### WebAuthn

#### Resolved Issues

- Fixed `navigator.credentials.create()` rejects with “NotAllowedError: Operation Failed” after a conditional UI request is aborted. ([273918@main](https://commits.webkit.org/273918@main))  (109936742)

### WebGL

#### New Features

- Enabled support for `EXT_texture_mirror_clamp_to_edge`, `WEBGL_render_shared_exponent`, and `WEBGL_stencil_texturing`. ([273645@main](https://commits.webkit.org/273645@main))  (121835897)

### WebRTC

#### New Features

- Added support for missing WebRTC stats. ([273643@main](https://commits.webkit.org/273643@main))  (121594743)

#### Resolved Issues

- Fixed a bug that prevented HTML canvas elements from always being marked dirty on initialization. This could cause some video effects to have choppy animations.  (121257960)
- Fixed VideoTrackGenerator writer to close when its generator track (and all its clones) are stopped. ([273778@main](https://commits.webkit.org/273778@main))  (121835553)

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