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# Safari Technology Preview 205 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: CSS, HTML, JavaScript, Lockdown Mode, SVG, Tables, Text, Web API, Web Driver, Web Extensions, and WebAssembly.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 205 is now [available for download](https://developer.apple.com/safari/resources/) for macOS Sequoia beta and macOS Sonoma. 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: [283688@main…284049@main](https://github.com/WebKit/WebKit/compare/d1370d8d93b0d9d13bd9f3b0a93c7b8662bbc75f...8f21d464d440967c7df58cbe9050dfa2ebdc9fe2).

### HTML

#### Resolved Issues

- Fixed adding an unexpected download failure when no placeholder URL is provided. ([284157@main](https://commits.webkit.org/284157@main))  (136378962)

### JavaScript

#### New Features

- Added support for `Math.sumPrecise`. ([283774@main](https://commits.webkit.org/283774@main))  (131580043)
- Added support for `Iterator.prototype.reduce`. ([283697@main](https://commits.webkit.org/283697@main))  (136064316)

#### Resolved Issues

- Fixed: Updated `Intl.DurationFormat#resolvedOptions` to the latest specification. ([283901@main](https://commits.webkit.org/283901@main))  (136276429)
- Fixed Iterator Helpers methods to not iterate an array. ([283933@main](https://commits.webkit.org/283933@main))  (136303997)

### Lockdown Mode

#### New Features

- Enabled Lockdown Mode Safe Fonts to try parsing web fonts with a safe font parser in Lockdown Mode. While the safe parser is enabled the list of allowed fonts won’t be used.  ([283951@main](https://commits.webkit.org/283951@main))  (125621507)

### SVG

#### Deprecations

- Removed the SVG 1.1 kerning property. ([283718@main](https://commits.webkit.org/283718@main))  (116965514)

### Tables

#### Resolved Issues

- Fixed table row direction to be determined by the table’s direction, not the section. ([283875@main](https://commits.webkit.org/283875@main))  (99343532)

### Text

#### Resolved Issues

- Fixed: The changes for GB18030-2022 now properly impact GBK as well, as required by the Encoding Standard. ([283987@main](https://commits.webkit.org/283987@main))  (136368583)

### Web API

#### Resolved Issues

- Fixed the `onrejectionhandled` and `onunhandledrejection` event handler attributes to work correctly on body and frameset elements. ([283698@main](https://commits.webkit.org/283698@main))  (135401362)

### Web Driver

#### Resolved Issues

- Fixed chorded mouse interactions by ensuring input dispatch logic correctly interprets successive mousepress or mouserelease actions with different `button` values. ([283790@main](https://commits.webkit.org/283790@main))  (128669517)

### Web Extensions

#### Resolved Issues

- Fixed an issue to restore lost Safari Web Extension data.  (136159837)

### WebAssembly

#### New Features

- Added support for the new Wasm Exception Specification. ([283954@main](https://commits.webkit.org/283954@main))  (131409318)

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