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  "title" : "Safari Technology Preview 177 Release Notes"
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# Safari Technology Preview 177 Release Notes

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

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 177 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: [266419@main…266623@main](https://github.com/WebKit/WebKit/compare/3cb928bc8c15b75620a673dd9e08ba2d54e3c94a...b501ddbb9b8992bc137e5f9250604322ff272598).

### Web Inspector

- Fixed broken search functionality ([266783@main](https://commits.webkit.org/266783@main), [266820@main](https://commits.webkit.org/266820@main), [266802@main](https://commits.webkit.org/266802@main))

### CSS

- Fixed `mod()` evaluation ([266485@main](https://commits.webkit.org/266485@main))
- Fixed `round()` evaluation when the number is a multiple of the step ([266504@main](https://commits.webkit.org/266504@main))
- Fixed computing the correct `overflow-x` and `overflow-y` values for `<table>` elements ([266560@main](https://commits.webkit.org/266560@main))

### Rendering

- Fixed out-of-flow `<br>` to not trigger a line break ([266475@main](https://commits.webkit.org/266475@main))

### Popover

- Fixed popover incorrectly auto-hiding when using shadow DOM ([266457@main](https://commits.webkit.org/266457@main))

### Media

- Fixed fullscreen ready check to remove the hierarchy requirement ([266426@main](https://commits.webkit.org/266426@main))
- Fixed videos disappearing when switching from landscape to portrait ([266531@main](https://commits.webkit.org/266531@main))
- Fixed pausing media playback after suspending media playback to correctly pause after media playback is unsuspended ([266590@main](https://commits.webkit.org/266590@main))

### JavaScript

- Optimized `Array#splice` to skip result array creation if it is not used at all ([266591@main](https://commits.webkit.org/266591@main))

### Web API

- Fixed intermittent removal of `adoptedStyleSheet` CSSStyleSheet instances when assigning an `adoptedStyleSheet` array ([266464@main](https://commits.webkit.org/266464@main))
- Fixed keyboard scroll not stopping after pressing the down arrow if `keyup` is default prevented ([266425@main](https://commits.webkit.org/266425@main))
- Fixed `window.postMessage` with OffscreenCanvas with an isolated world message listener ([266465@main](https://commits.webkit.org/266465@main))

### Accessibility

- Fixed non-accessible content within iframes with ARIA roles ([266506@main](https://commits.webkit.org/266506@main))
- Fixed VoiceOver word echo on text inputs with a `combobox` role ([266569@main](https://commits.webkit.org/266569@main))

### Apple Pay

- Deprecated `enabled` in favor of `available` in `shippingContactEditingMode` ([266493@main](https://commits.webkit.org/266493@main))

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