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# Safari Technology Preview 178 Release Notes

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

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 178 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: [266624@main…267312@main](https://github.com/WebKit/WebKit/compare/d87a70ea254bd9a81675a7fe688be40987b6a621...dc989b3ef737547949c45f39dc996f0850fe862f).

### Web Inspector

- Added color palette with CSS variables in color picker ([266794@main](https://commits.webkit.org/266794@main))
- Moved the details sidebar to the bottom when Web Inspector is too narrow ([266784@main](https://commits.webkit.org/266784@main))

### CSS

- Implemented `counter-set` property ([267137@main](https://commits.webkit.org/267137@main))
- Fixed counter values to prevent them from overflowing or underflowing ([266817@main](https://commits.webkit.org/266817@main))
- Fixed `<resolution>` to not accept negative resolutions for `@property`  ([267134@main](https://commits.webkit.org/267134@main))
- Fixed `currentcolor` to correctly inherit computed `:visited` style ([267139@main](https://commits.webkit.org/267139@main))
- Fixed `color-mix()` to respect `:visited` style to resolve “currentcolor” ([267271@main](https://commits.webkit.org/267271@main))
- Fixed baseline aligned flex items to also be aligned using their fallback alignment ([267026@main](https://commits.webkit.org/267026@main))
- Fixed `border-image` to fall back to the `border` property if the image is invalid ([266749@main](https://commits.webkit.org/266749@main))
- Fixed the `scripting` media query to never match `initial-only` ([267198@main](https://commits.webkit.org/267198@main))
- Fixed `font-size-adjust` toggling font sizes for `system-ui` font ([266771@main](https://commits.webkit.org/266771@main))
- Fixed `:user-invalid` and `:user-valid` interactions with form reset and submission ([266702@main](https://commits.webkit.org/266702@main))
- Added the support for mixed percentage and length/number arguments in CSS step functions ([267072@main](https://commits.webkit.org/267072@main))

### CSS Container Queries

- Fixed container unit resolution to check if the selected container is eligible ([267192@main](https://commits.webkit.org/267192@main))
- Fixed `container-name` to use scoped names ([267163@main](https://commits.webkit.org/267163@main))
- Fixed container selection for container units in pseudo-elements ([267197@main](https://commits.webkit.org/267197@main))
- Fixed container query with font units to invalidate when the font changes ([267258@main](https://commits.webkit.org/267258@main))

### JavaScript

- Enabled `import` attributes ([266957@main](https://commits.webkit.org/266957@main))
- Added support for `Intl.NumberFormat`’s FormatApproximately operation ([266645@main](https://commits.webkit.org/266645@main))
- Changed `Intl.DurationFormat` digital’s default from narrow to short ([266891@main](https://commits.webkit.org/266891@main))
- Fixed a positive look-behind RegExp with alternatives of different minimum lengths ([266912@main](https://commits.webkit.org/266912@main))
- Increased `minimumFractionDigits` and `maximumFractionDigits` limit from 20 to 100 ([266879@main](https://commits.webkit.org/266879@main))
- Updated `Intl.DateTimeFormat`’s to obtain options only once, matching spec changes ([266868@main](https://commits.webkit.org/266868@main))
- Updated `Intl.NumberFormat` and `Intl.PluralRules` `roundingIncrement` handling ([267123@main](https://commits.webkit.org/267123@main))

### SVG

- Added the missing default value `translate` for `animateTransform` ([266758@main](https://commits.webkit.org/266758@main))
- Fixed `paint-order` property to inherit ([267002@main](https://commits.webkit.org/267002@main))
- Fixed SVG filters to prevent them from leaking visited hyperlinks ([266683@main](https://commits.webkit.org/266683@main))

### Accessibility

- Fixed an issue where `innerHTML` and `innerText` changes to labels did not update their corresponding input element’s accessibility title ([266919@main](https://commits.webkit.org/266919@main))

### Media

- Added support for negative timestamps of TextTrackCue ([267042@main](https://commits.webkit.org/267042@main))
- Fixed vertical multiline WebVTT captions getting cut off ([267162@main](https://commits.webkit.org/267162@main))

### IntersectionObserver

- Fixed edge cases in parsing options ([266856@main](https://commits.webkit.org/266856@main))

### Web API

- Enabled Fetch Priority by default ([267196@main](https://commits.webkit.org/267196@main))
- Enabled requestIdleCallback ([267023@main](https://commits.webkit.org/267023@main), [266750@main](https://commits.webkit.org/266750@main))
- Made event loop to execute idle callbacks at the end of each task ([266877@main](https://commits.webkit.org/266877@main))
- Enabled responsive images in `<link rel=preload>` ([266787@main](https://commits.webkit.org/266787@main))
- Added the `change` event for the Cookie Store API ([266850@main](https://commits.webkit.org/266850@main))
- Added more restrictions for top-frame navigations by a third-party iframe ([266666@main](https://commits.webkit.org/266666@main))
- Added support for `from-image` to ImageBitmapOptions ([266893@main](https://commits.webkit.org/266893@main))
- Changed navigable target names to `_blank` if they have dangling markup ([267154@main](https://commits.webkit.org/267154@main))
- Fixed `ServiceWorkerRegistration` data deletion ([266882@main](https://commits.webkit.org/266882@main))
- Fixed details element to use `ToggleEvent` for toggle events ([267076@main](https://commits.webkit.org/267076@main))
- Fixed `SpeechSynthesisUtterance` to not get GC’ed if there is a pending event ([267161@main](https://commits.webkit.org/267161@main))
- Added the support for key pair checks for Ed25519 in WebCrypto ([267184@main](https://commits.webkit.org/267184@main))
- Added basic support for `SVGImageElement` in `createImageBitmap` ([267218@main](https://commits.webkit.org/267218@main))
- Fixed `<a>` and `<area>` origin getters to return an empty string for non-parsable URLs ([267222@main](https://commits.webkit.org/267222@main))
- Fixed `<a>` and `<area>` protocol setters for non-parsable URLs ([267265@main](https://commits.webkit.org/267265@main))

### WebGL

- Fixed WebGL to not send a non-standard `webglcontextchanged` event ([266861@main](https://commits.webkit.org/266861@main))

---

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