Apple has released Safari Technology Preview 244, bringing a large batch of bug fixes, performance improvements, and web technology updates for developers and advanced users testing upcoming Safari features. The experimental browser update is now available for macOS Sequoia and macOS Tahoe.
Safari Technology Preview acts as Apple’s testing platform for future Safari releases, giving developers early access to WebKit improvements before they roll out publicly. While it is designed with developers in mind, anyone can install and use the browser alongside the standard Safari app without needing a developer account.
Safari Technology Preview 244 focuses heavily on CSS, rendering, JavaScript performance, accessibility, and WebGPU reliability. Apple added support for transform-aware anchor positioning and expanded the position-anchor CSS property with new values. The release also fixes a long list of layout and rendering bugs affecting flexbox, aspect-ratio calculations, RTL text rendering, scroll containers, and :has() selector invalidation.
The update also improves JavaScript and WebAssembly performance. Apple fixed slower module resolution behavior, improved TypedArray search performance with SIMD optimizations, and resolved a WebAssembly regression that caused vector-width corruption in certain SIMD workloads.
Accessibility fixes are another major part of Safari Technology Preview 244. Apple resolved multiple VoiceOver issues, including incorrect cursor positioning and skipped content during line-by-line reading. Interactive SVG elements with nested title tags now expose proper accessible names as expected.
WebGPU and WebGL received important fixes as well. Apple restored missing WebGPU limits and fixed issues with the GPUDevice.onuncapturederror event handler. WebGL updates address compressed texture validation problems, incorrect error reporting, and state reset issues after context loss.
Safari Technology Preview 244 also introduces improvements for web extensions and media playback. Extensions can now propagate user gestures through APIs like sendMessage(), connect(), and executeScript(), allowing actions such as media playback to work more reliably. Apple also added support for synchronized video playback using genlock on macOS.
Other fixes in the release cover Networking, HTML, Forms, MathML, SVG, Storage, Security, Web Inspector, and Scrolling. Apple says the update includes WebKit changes between builds 312008 and 313209.
Users who already have Safari Technology Preview installed can update through System Settings > General > Software Update. New users can download the browser directly from Apple’s Safari Technology Preview website.
Read the full release notes here.
