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# Safari Technology Preview 174 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: CSS, CSS Container Queries, Layout, JavaScript, Media, Popover, Accessibility, SVG, Web API, and WASM.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 174 is now [available for download](https://developer.apple.com/safari/resources/) for macOS Sonoma beta 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: [265305@main…265693@main](https://github.com/WebKit/WebKit/compare/59a3c15be1a8d5680e7fdcfc70d87117ff53e014...68167894313ea917099c52a92e4b1ab03a277abf).

### CSS

- Added support for `contain-intrinsic-size: auto none`  property syntax ([265617@main](https://commits.webkit.org/265617@main))
- Fixed `text-overflow: ellipsis` so it works with  `overflow: clip` ([265445@main](https://commits.webkit.org/265445@main))
- Fixed `cjk-earthly-branch` and `cjk-heavenly-stem` counter styles to fallback to `cjk-decimal` ([265474@main](https://commits.webkit.org/265474@main))
- Fixed `inline-flex` and `inline-grid` boxes to stop propagating underlines to align with other browsers ([265471@main](https://commits.webkit.org/265471@main))
- Fixed CSS accelerated animation handling with multiple effects on the stack ([265498@main](https://commits.webkit.org/265498@main))
- Fixed cursor style to respect explicitly set cursor type over system default ([265597@main](https://commits.webkit.org/265597@main))

### CSS Container Queries

- Fixed container units in a container query to evaluate against the ancestor container ([265583@main](https://commits.webkit.org/265583@main))
- Fixed container units to consider writing mode for unit resolution ([265654@main](https://commits.webkit.org/265654@main))

Fixed how text decorations propagate into tables to align with other browsers ([265488@main](https://commits.webkit.org/265488@main))

### Layout

- Fixed list alignment when a list item has a flex container ([265464@main](https://commits.webkit.org/265464@main))
- Fixed font size to allow use of fractional pixel values ([265657@main](https://commits.webkit.org/265657@main))
- Fixed `bordercolor` attribute on table elements to not create a visible border ([265670@main](https://commits.webkit.org/265670@main))

### JavaScript

- Renamed `.groupByToMap()` on Array to  `.groupBy()`  on Object and Map in order to align with latest TC-39 proposal ([265632@main](https://commits.webkit.org/265632@main))

### Media

- Added support for WebCodecs temporal `scalabilityMode` for software codecs, including parsing and error handling ([265561@main](https://commits.webkit.org/265561@main))
- Added support for WebM files with no track ID ([265425@main](https://commits.webkit.org/265425@main))
- Updated  `VTTCue` to match latest W3C specification, including support for CSS updated default CSS properties, as well as support for `vh`, `vw`, `cqh`, and `cqw` units. ([265596@main](https://commits.webkit.org/265596@main))

### Popover

- Fixed `togglePopover()` to always throw an exception if it’s disconnected or not a popover ([265589@main](https://commits.webkit.org/265589@main))

### Accessibility

- Improved accessibility for tables and table components with `display`: `flex`, `grid`, `block`, `inline-block`, and `contents` ([265486@main](https://commits.webkit.org/265486@main))
- Prioritized HTML `required` attribute over `aria-required` when both are present ([265552@main](https://commits.webkit.org/265552@main))

### SVG

- Fixed `dominant-baseline` CSS property to be inherited ([265525@main](https://commits.webkit.org/265525@main))
- Fixed references for SVG fragments in shadow DOM trees ([265565@main](https://commits.webkit.org/265565@main))

### Web API

- Fixed constructing a `SharedWorker` in a detached document so it throws an exception ([265483@main](https://commits.webkit.org/265483@main))
- Removed artificial memory limit for `canvas` context, given it the same memory restrictions as other Web features ([265628@main](https://commits.webkit.org/265628@main))

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