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# Safari Technology Preview 159 Release Notes

Preview the latest web technology updates including: WebAssembly, JavaScript, and Rendering.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 159 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 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: [256139@main…256265@main](https://github.com/WebKit/WebKit/compare/bf37b793b7fccccf11fe519c1b68901020b5b406...353ab60dcb1be40f2df94cb4204539e3090cf64f)

**Note:** Shared Tab Groups and syncing for Tab Groups, Website Settings, and Web Extensions are not enabled in this release.

### WebAssembly

- Fixed error message for `local.get` ([256176@main](https://commits.webkit.org/256176@main))

### JavaScript

- Changed to allow variables with the same name as the class in its static block ([256311@main](https://commits.webkit.org/256311@main))

### Rendering

- Fixed floating boxes overlapping their margin boxes ([256183@main](https://commits.webkit.org/256183@main))
- Fixed rendering artifacts when presenting a fullscreen video ([256251@main](https://commits.webkit.org/256251@main))

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