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# Safari Technology Preview 176 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: CSS, Rendering, Accessibility, Media, and Web API.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 176 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: [266088@main…266418@main](https://github.com/WebKit/WebKit/compare/3ae98fa2c02b272e3e55c4e0c324d01da17cb5dc...57717fd0d5abf106eddd9881f3eb8efbd3957f92).

### CSS

- Added support for `contain-intrinsic-size: inherit` ([266100@main](https://commits.webkit.org/266100@main))
- Implemented `linear(...)` timing function for CSS animations & transitions ([266195@main](https://commits.webkit.org/266195@main))
- Fixed `auto none` support for `contain-intrinsic-size` ([266136@main](https://commits.webkit.org/266136@main))
- Fixed computing `<hr>` `width` attribute set to `0` or `0px` ([266418@main](https://commits.webkit.org/266418@main))

### Rendering

- Fixed out-of-flow boxes not showing  ([266366@main](https://commits.webkit.org/266366@main))
- Fixed canvas not showing the results of `CanvasRenderingContext2D.putImageData` until a forced re-render ([266397@main](https://commits.webkit.org/266397@main))
- Fixed scrollbar not updating on CSS color-scheme change ([266176@main](https://commits.webkit.org/266176@main))
- Prevented invalidating columns when the entire table is being destroyed ([266344@main](https://commits.webkit.org/266344@main))

### Accessibility

- Fixed `display: contents` elements sometimes missing their children ([266407@main](https://commits.webkit.org/266407@main))
- Fixed incorrect accessible name from multiple `<label>` elements ([266151@main](https://commits.webkit.org/266151@main))
- Fixed unexpected speech synthesis behavior for unordered lists ([266383@main](https://commits.webkit.org/266383@main))

### Media

- Implemented automatic text track selection for `'metadata'` tracks ([266380@main](https://commits.webkit.org/266380@main))
- Fixed RTCRtpSender `maxFramerate` encoding parameter having no effect ([266128@main](https://commits.webkit.org/266128@main))
- Fixed updating time stamps on media controls to update while scrubbing the timeline ([266339@main](https://commits.webkit.org/266339@main))

### Web API

- Added support for the `title` attribute for pattern validation errors ([266311@main](https://commits.webkit.org/266311@main))
- Aligned `naturalWidth` and `naturalHeight` with spec, changing from `int` to `unsigned` ([266302@main](https://commits.webkit.org/266302@main))
- Changed to return opaque origin for `blob:` URL containing inner non-http(s): URL ([266247@main](https://commits.webkit.org/266247@main))
- Converted `embed hidden` into a proper boolean attribute ([266399@main](https://commits.webkit.org/266399@main))
- Fixed `ElementInternals.setFormValue(<nullish value>)` to clear the submission value ([266126@main](https://commits.webkit.org/266126@main))
- Fixed custom highlight logic for checking author and set text color ([266117@main](https://commits.webkit.org/266117@main))
- Fixed custom highlight text decoration to respect priority ([266184@main](https://commits.webkit.org/266184@main))
- Fixed emoji characters sometimes getting incorrectly drawn in text style ([266089@main](https://commits.webkit.org/266089@main))
- Fixed URL pathname and search setter incorrectly stripping trailing spaces ([266252@main](https://commits.webkit.org/266252@main))
- Handled focusability for plugin elements which have browsing context ([266286@main](https://commits.webkit.org/266286@main))
- Throttled `mousemove` events to one per rendering update ([266341@main](https://commits.webkit.org/266341@main))

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