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# Safari Technology Preview 165 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: Web Inspector, CSS, JavaScript, Layout, Forms, Web Animations, WebCrypto, WebGL, Loading, Web API, Accessibility, and Web Extensions.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 165 is now [available for download](https://webkit.org/downloads/) for macOS Monterey 12.3 or later and macOS Ventura. If you already have Safari Technology Preview installed, you can update it in the Software Update pane of System Preferences on macOS Monterey, or System Settings under General → Software Update on macOS Ventura.

This release includes WebKit changes between: [260164@main…260848@main](https://github.com/WebKit/WebKit/compare/2e7b4c711a574e8dd4ae8de0e2bac8a573e2439e...b0e1a9c1d9b3b952faa97d997c57d6358d11b79f).

### Web Inspector

- Added support for `color-mix` CSS values in the Styles details sidebar of the Elements tab ([260332@main](https://commits.webkit.org/260332@main))
- Added setting to always show rulers when highlighting elements ([260416@main](https://commits.webkit.org/260416@main))

### CSS

- Added support for `text-transform: full-size-kana` ([260307@main](https://commits.webkit.org/260307@main))
- Added support for `margin-trim` for floats in block containers that contain only block boxes ([260318@main](https://commits.webkit.org/260318@main))
- Added support for `x` units in `calc()` function ([260678@main](https://commits.webkit.org/260678@main))
- Added support to `image-set()` for resolution and type as optional arguments ([260796@main](https://commits.webkit.org/260796@main))
- Fixed `preserve-3d` not being applied to pseudo elements. ([260324@main](https://commits.webkit.org/260324@main))
- Fixed `opacity` not applying to dialog element `::backdrop` pseudo-class ([260556@main](https://commits.webkit.org/260556@main))
- Fixed the background to not propagate when `content: paint` is set on the body or root element ([260766@main](https://commits.webkit.org/260766@main))
- Fixed `table-layout: fixed` not being applied when `width` is `max-content` ([260501@main](https://commits.webkit.org/260501@main))
- Fixed `font-optical-sizing: auto` having no effect ([260447@main](https://commits.webkit.org/260447@main))

### JavaScript

- Added support for RegExp Duplicate Named Capture Groups ([260692@main](https://commits.webkit.org/260692@main))
- Changed `Intl.Locale` info proposals’ getters to methods to match the latest specification ([260412@main](https://commits.webkit.org/260412@main))
- Optimized Boolean constructor calls ([260816@main](https://commits.webkit.org/260816@main))
- Optimized Proxy [[Set]] trap ([260803@main](https://commits.webkit.org/260803@main))
- Optimized Bound function calls ([260303@main](https://commits.webkit.org/260303@main), [260494@main](https://commits.webkit.org/260494@main))
- Optimized `Reflect.get` ([260327@main](https://commits.webkit.org/260327@main))
- Optimized Proxy [[Get]] trap ([260282@main](https://commits.webkit.org/260282@main))
- Optimized WebAssembly SIMD operations ([260223@main](https://commits.webkit.org/260223@main), [260206@main](https://commits.webkit.org/260206@main), [260239@main](https://commits.webkit.org/260239@main))
- Replaced narrow-no-break spaces from `Intl.DateTimeFormat` with ASCII spaces for web compatibility ([260179@main](https://commits.webkit.org/260179@main))
- Updated RegExp UnicodeData to 15.0.0 ([260607@main](https://commits.webkit.org/260607@main))

### Layout

- Fixed accounting of margins in multi-column layout before forced breaks ([260510@main](https://commits.webkit.org/260510@main))
- Fixed floats with clear to not be placed incorrectly ([260674@main](https://commits.webkit.org/260674@main))

### Media

- Fixed `SourceBuffer.timestampOffset` not behaving correctly with webm content ([260822@main](https://commits.webkit.org/260822@main))
- Fixed HDR data to no longer be clipped in AVIF images ([260512@main](https://commits.webkit.org/260512@main))

### Forms

- Fixed resetting the value of an `input` `type=file` to `null` to make the input invalid ([260688@main](https://commits.webkit.org/260688@main))
- Fixed `minlength`/`maxlength` attributes to rely on code units instead of grapheme clusters ([260838@main](https://commits.webkit.org/260838@main))

### Web Animations

- Added support for the `length` property of `CSSKeyframesRule` ([260400@main](https://commits.webkit.org/260400@main))
- Changed animation of `mask-image` to be discrete ([260756@main](https://commits.webkit.org/260756@main))
- Fixed custom properties not being treated as valid in the shorthand `animation` property ([260759@main](https://commits.webkit.org/260759@main))
- Fixed `transition-property: all` not applying to custom properties ([260384@main](https://commits.webkit.org/260384@main))

### WebCrypto

- Fixed Secure Curves not having a `namedCurve` property ([260599@main](https://commits.webkit.org/260599@main))

### WebGL

- Fixed restored WebGL context not being visible until layout ([260693@main](https://commits.webkit.org/260693@main))

### Loading

- Fixed lazily loaded frames to get a `contentWindow`/`contentDocument` as soon as they get inserted into the document ([260713@main](https://commits.webkit.org/260713@main))
- Fixed frames to not be lazily loaded if they have an invalid or `about:blank` URL ([260612@main](https://commits.webkit.org/260612@main))

### Web API

- Added `Headers.prototype.getSetCookie`. ([260533@main](https://commits.webkit.org/260533@main))
- Added support for `link` `rel=modulepreload` ([260761@main](https://commits.webkit.org/260761@main), [260709@main](https://commits.webkit.org/260709@main), [260659@main](https://commits.webkit.org/260659@main))
- Fixed `location.href` to throw a `DOMException` “`SyntaxError`” on failing to parse the URL ([260539@main](https://commits.webkit.org/260539@main))

### Accessibility

- Fixed `aria-errormessage` to not be exposed when `aria-invalid` is `false` ([260545@main](https://commits.webkit.org/260545@main))
- Fixed text associated with various types of elements not being exposed ([260521@main](https://commits.webkit.org/260521@main))
- Fixed invalid summary elements to not be exposed as interactive ([260546@main](https://commits.webkit.org/260546@main))
- Fixed some inputs not being treated as invalid despite being rendered as such ([260544@main](https://commits.webkit.org/260544@main))

### Web Extensions

- Fixed Content Blocker API ignoring some CSS selectors with uppercase letters ([260638@main](https://commits.webkit.org/260638@main))

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