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# Safari Technology Preview 191 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: Accessibility, Authentication, CSS, Forms, History, JavaScript, Lockdown Mode, Media, SVG, Web API, Web Inspector, and WebRTC.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 191 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: [274942@main…276246@main](https://github.com/WebKit/WebKit/compare/a691187c506e9f19e2a61adbf52585560d704d12...b2ec60c7d5b8ab1ded9edfae217285f4059aa28d).

### Accessibility

#### New Features

- Added support for `ariaBrailleLabel` and `ariaBrailleRoleDescription` element reflection properties. ([275591@main](https://commits.webkit.org/275591@main))  (123926949)

#### Resolved Issues

- Fixed a bug preventing VoiceOver word echoing in some text fields. ([275694@main](https://commits.webkit.org/275694@main))  (122451549) (FB13592798)
- Fixed time input accessibility by adding labels to subfields. ([275301@main](https://commits.webkit.org/275301@main))  (122590568)
- Fixed `datetime` values being exposed to assistive technologies in the wrong timezone. ([275265@main](https://commits.webkit.org/275265@main))  (123522296)
- Fixed time control accessibility by adding a label to the meridiem component. ([276195@main](https://commits.webkit.org/276195@main))  (123781149)
- Fixed wrong `datetime` value being exposed to assistive technologies for `datetime-local` inputs. ([275548@main](https://commits.webkit.org/275548@main))  (123803281)
- Fixed the computed role for these elements: `dd`, `details`, `dt`, `em`, `hgroup`, `option`, `s`, and `strong`. ([276240@main](https://commits.webkit.org/276240@main))  (124641956)

### Authentication

#### Resolved Issues

- Fixed `excludeCredentials` property being ignored during a passkey registration request. ([276006@main](https://commits.webkit.org/276006@main))  (124405037)

### CSS

#### Resolved Issues

- Fixed `getComputedStyle()` to work with functional pseudo-elements like `::highlight()`. ([274846@main](https://commits.webkit.org/274846@main))  (117864743)
- Fixed changing color scheme to update gradients with system colors or `light-dark()`. ([275645@main](https://commits.webkit.org/275645@main))  (121285450)
- Fixed `:empty` selector to work with animations. ([275832@main](https://commits.webkit.org/275832@main))  (122838142)
- Fixed starting style to inherit from its parent’s after-change style. ([275061@main](https://commits.webkit.org/275061@main))  (123302667)
- Fixed CSS container style queries to allow `!important`. ([275104@main](https://commits.webkit.org/275104@main))  (123374708)
- Fixed preserving whitespace when serializing custom properties. ([275236@main](https://commits.webkit.org/275236@main))  (123491915)
- Fixed updating style correctly for non-inherited custom property mutations. ([275445@main](https://commits.webkit.org/275445@main))  (123645196)
- Fixed element removed by parent to end up losing the last remembered size. ([275606@main](https://commits.webkit.org/275606@main))  (123975513)
- Fixed resolving container units in style queries. ([275689@main](https://commits.webkit.org/275689@main))  (124058441)

### Forms

#### Resolved Issues

- Fixed native text fields becoming invisible in dark mode. ([275363@main](https://commits.webkit.org/275363@main))  (123658326)
- Fixed `<select multiple>` scrollbars to match the used color scheme. ([275505@main](https://commits.webkit.org/275505@main))  (123807167)
- Fixed fallback native `<select>` rendering in dark mode. ([275532@main](https://commits.webkit.org/275532@main))  (123845293)

### JavaScript

#### Resolved Issues

- Fixed `String.prototype.replace` to not take the fast path if the pattern is RegExp Object and the `lastIndex` is not numeric. ([275255@main](https://commits.webkit.org/275255@main))  (101122567)
- Fixed `Symbol.species` getters to not share a single JS Function. ([275064@main](https://commits.webkit.org/275064@main))  (120416817)
- Fixed try/catch to not intercept errors originated in `[[Construct]]` of derived class. ([275353@main](https://commits.webkit.org/275353@main))  (121959506)
- Fixed TypedArray sorting methods to have a special-case for camparator returning `false`. ([276130@main](https://commits.webkit.org/276130@main))  (122093956)
- Fixed `emitReturn()` to load `this` value from arrow function lexical environment prior to the TDZ check. ([275425@main](https://commits.webkit.org/275425@main))  (122430056)
- Fixed NFKC normalization to work with Latin-1 characters. ([275062@main](https://commits.webkit.org/275062@main))  (123328161)
- Fixed parsing of private names with Unicode start characters. ([275152@main](https://commits.webkit.org/275152@main))  (123425805)
- Fixed `instanceof` to not get RHS prototype when LHS is primitive. ([275318@main](https://commits.webkit.org/275318@main))  (123629166)
- Fixed bracket update expression to resolve property key at most once. ([275531@main](https://commits.webkit.org/275531@main))  (123872374)
- Fixed bracket compound assignement to resolve the property key at most once. ([276014@main](https://commits.webkit.org/276014@main))  (124420301)

### Lockdown Mode

#### Resolved Issues

- Fixed: Updated the trusted list of fonts to address missing glyphs on some sites. ([275705@main](https://commits.webkit.org/275705@main))  (123658932)

### Media

#### New Features

- Added support for WebCodecs AV1 when an AV1 hardware decoder is available. ([275174@main](https://commits.webkit.org/275174@main))  (123433815)

#### Resolved Issues

- Fixed audio distortion over internal speakers when streaming content in web browsers. ([275262@main](https://commits.webkit.org/275262@main))  (122590884)
- Fixed playback for MSE videos on some sites. ([275443@main](https://commits.webkit.org/275443@main))  (123528095)
- Fixed firing `loadeddata` events for `<audio>` and `<video>` on page load. ([275997@main](https://commits.webkit.org/275997@main))  (124079735) (FB13675360)

### SVG

#### Resolved Issues

- Fixed returning the initial value for the SVG gradient `stop-color` if it is not rendered in the page. ([274997@main](https://commits.webkit.org/274997@main))  (123262508)
- Fixed the SVG marker segment calculations if the marker path consists of sub-paths. ([275167@main](https://commits.webkit.org/275167@main))  (123434203)

### Web API

#### Resolved Issues

- Fixed `cssText `setter to change the `style` attribute when the serialization differs. ([276176@main](https://commits.webkit.org/276176@main))  (29861252) (FB5535475)
- Fixed mousemove events in an iframe when the mouse is clicked from outside the iframe and then moves into it while the button is held down. ([275157@main](https://commits.webkit.org/275157@main))  (120540148) (FB13517196)
- Fixed `getGamepads()` to no longer trigger an insecure contexts warning. ([274962@main](https://commits.webkit.org/274962@main))  (123039555)

#### Deprecations

- Removed `HashChangeEvent`’s non-standard `initHashChangeEvent()` method. ([276232@main](https://commits.webkit.org/276232@main))  (124736521)

### Web Inspector

#### Resolved Issues

- Fixed expanded sections of Storage to not collapse. ([275783@main](https://commits.webkit.org/275783@main))  (107687975)
- Fixed CSS font property values marked `!important` not getting overridden when using the interactive editing controls. ([275389@main](https://commits.webkit.org/275389@main))  (112080113)
- Fixed runtimes to be aligned in the Audit tab. ([275298@main](https://commits.webkit.org/275298@main))  (121810292)
- Fixed info and debug buttons not appearing in the Console Tab until new console messages are displayed. ([275914@main](https://commits.webkit.org/275914@main))  (122923625)
- Fixed remembering the message type selection in the Console tab. ([275143@main](https://commits.webkit.org/275143@main))  (122924275)
- Fixed autocomplete for the `text-indent` property suggesting prefixed properties instead of `each-line` or `hanging`. ([274979@main](https://commits.webkit.org/274979@main))  (123240715)
- Fixed `background` autocompletion suggestion to include `repeating-conic-gradient`. ([275160@main](https://commits.webkit.org/275160@main))  (123428709)

### WebRTC

#### Resolved Issues

- Fixed black stripes with screen sharing windows. ([275736@main](https://commits.webkit.org/275736@main), [275742@main](https://commits.webkit.org/275742@main), [275789@main](https://commits.webkit.org/275789@main))  (123492622)
- Fixed black stripes with getDisplayMedia captured windows when the window is resized. ([275794@main](https://commits.webkit.org/275794@main))  (124131045)

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