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# Safari Technology Preview 233 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: Animations, HTML, MathML, Rendering, Web API, and Web Inspector.

## Overview

[Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 233 is now [available for download](https://developer.apple.com/safari/resources/) for macOS Tahoe and macOS Sequoia. 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: [302450@main…303091@main](https://github.com/WebKit/WebKit/compare/4fe84786ee93517c90add3476e69754996277119...88502d8ee638d95e6a69f16788dca8675a99f923).

### Animations

#### Resolved Issues

- Fixed incorrect overlap calculations for transform animations including `translate`, `scale`, and `rotate` properties. ([303045@main](https://commits.webkit.org/303045@main))  (88383253)

### HTML

#### New Features

- Added support for enhanced HTML select parsing to allow `<select>` elements to include `<optgroup>`, `<option>`, and `<hr>` at deeper nesting levels. ([302480@main](https://commits.webkit.org/302480@main))  (163927485)

### MathML

#### New Features

- Added support for the MathML `scriptlevel` attribute, mapping it to CSS `math-depth` as a presentational hint. ([302841@main](https://commits.webkit.org/302841@main))  (164469677)

#### Resolved Issues

- Fixed `mpadded` elements in RTL (`dir="rtl"`) to respect `lspace`. ([303070@main](https://commits.webkit.org/303070@main))  (164740784)

### Rendering

#### Resolved Issues

- Fixed an issue where fixed positioned elements were not rendered correctly in right-to-left pages using the `vertical-rl` writing mode. ([302542@main](https://commits.webkit.org/302542@main))  (161712734)

### Web API

#### New Features

- Added support for reading `Blob.stream()` with a BYOB (`getReader({mode:'byob'})`) reader. ( [302787@main](https://commits.webkit.org/302787@main) )  (164307723)

#### Resolved Issues

- Fixed Trusted Types to correctly send CSP violation reports when a default policy returns an invalid `javascript:` URL or throws an exception. ([302543@main](https://commits.webkit.org/302543@main))  (160960418)
- Fixed `NavigateEvent` to correctly fire an `AbortSignal` when a navigation is aborted. ([302591@main](https://commits.webkit.org/302591@main))  (163957784)
- Fixed `NavigateEvent.sourceElement` to correctly reference elements from different browsing contexts. ([302504@main](https://commits.webkit.org/302504@main))  (163962362)

### Web Inspector

#### New Features

- Added support for capturing `console.screenshot` images within a `Worker`, including handling of `ImageData`, `ImageBitmap`, `OffscreenCanvas`, various `CanvasRenderingContext` types, and valid base64 `data:` URLs. ([302778@main](https://commits.webkit.org/302778@main))  (98223234)

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