# Safari Technology Preview 217 Release Notes Learn about the latest web technology updates in Safari Technology Preview: Accessibility, CSS, Forms, JavaScript, Media, Rendering, SVG, Tables, Web API, Web Extensions, Web Inspector, and WebRTC. ## Overview [Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 217 is now [available for download](https://developer.apple.com/safari/resources/) for macOS Sequoia 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: [292535@main…293326@main](https://github.com/WebKit/WebKit/compare/8c0057018318f586ac0bf01ff84047623750327f...ecc55c4f49e6126b4c4730b9be044dd5e44a9067) ### CSS #### Resolved Issues - Fixed `@scope` to create a style nested context. ([292821@main](https://commits.webkit.org/292821@main)) (148101373) - Fixed changing `content-visibility` from `visible` to `hidden` to repaint correctly. ([292960@main](https://commits.webkit.org/292960@main)) (148273903) - Fixed `color` to not be a high-priority property. ([293082@main](https://commits.webkit.org/293082@main)) (148361501) ### Forms #### Resolved Issues - Fixed `setValidity` of `ElementInternals` to handle missing optional `anchor` parameter. ([292770@main](https://commits.webkit.org/292770@main)) (123744294) ### JavaScript #### Resolved Issues - Fixed performance of `Math.hypot()` that was significantly slower than `Math.sqrt()`. ([292549@main](https://commits.webkit.org/292549@main)) (141821484) - Fixed `Array#indexOf` and `Array#includes` to treat `+0` and `-0` as the same value. ([293134@main](https://commits.webkit.org/293134@main)) (148472519) ### Media #### Resolved Issues - Fixed subtitle tracks with no `srclang` to be shown with the correct label. ([292577@main](https://commits.webkit.org/292577@main)) (147722563) ### Rendering #### Resolved Issues - Fixed the text indicator sometimes getting clipped during a bounce animation. ([292612@main](https://commits.webkit.org/292612@main)) (147602900) - Fixed geometry values inside `content-visibility: hidden` subtrees. ([293267@main](https://commits.webkit.org/293267@main)) (148553259) - Fixed not marking `content-visibility: hidden` content for layout when targeting `content-visibility: auto`. ([293304@main](https://commits.webkit.org/293304@main)) (148663896) ### SVG #### Resolved Issues - Fixed: Improved handling of SVG images with subresources. ([293259@main](https://commits.webkit.org/293259@main)) (148607855) ### Tables #### Resolved Issues - Fixed table layout to only be triggered when `inline-size` is not `auto`. ([292536@main](https://commits.webkit.org/292536@main)) (147636653) ### Web API #### New Features - Added support for scrollMargin in IntersectionObserver. ([293306@main](https://commits.webkit.org/293306@main)) (117527880) - Added support for the `alg` parameter when importing or exporting Edward’s-curve based JSON Web Keys in WebCrypto. ([293089@main](https://commits.webkit.org/293089@main)) (147323269) ### Web Extensions #### Resolved Issues - Fixed `"excludeMatches"` array in `scripting.registerContentScripts()` API getting ignored in Safari web extensions. ([293106@main](https://commits.webkit.org/293106@main)) (145489255) (FB16590857) ### Web Inspector #### New Features - Added support for exporting and importing data from worker targets in the Timelines tab. ([292991@main](https://commits.webkit.org/292991@main)) (145330533) - Added a a badge for `` to quickly jump to the assigned node in the Elements tab. ([292966@main](https://commits.webkit.org/292966@main)) (148297936) #### Resolved Issues - Fixed a performance issue when blackboxing a large number of sourcemaps. ([292997@main](https://commits.webkit.org/292997@main)) (148116377) ### WebRTC #### New Features - Added support for exposing CSRC information for RTCEncodedVideoStream. ([293088@main](https://commits.webkit.org/293088@main)) (76548862) - Added serialisation of RTCEncodedAudioFrame and RTCEncodedVideoFrame. ([293185@main](https://commits.webkit.org/293185@main)) (148244334) - Added support for `ImageCapture.grabFrame`. ([293243@main](https://commits.webkit.org/293243@main)) (148425176) #### Resolved Issues - Fixed `enumerateDevices` returning devices as available when permissions are denied. ([292921@main](https://commits.webkit.org/292921@main)) (147313922) - Fixed `getUserMedia` not using the correct camera or microphone if devices change while user is answering the permission prompt. ([292696@main](https://commits.webkit.org/292696@main)) (147762070) - Fixed` enumerateDevices` to not check for device permission. ([293003@main](https://commits.webkit.org/293003@main)) (148094614) - Fixed WebRTC encoded transform to transfer to the RTC encoded frame array buffer. ([293232@main](https://commits.webkit.org/293232@main)) (148343876) - Fixed RTC encoded frame timestamp should be persistent. ([293238@main](https://commits.webkit.org/293238@main)) (148580865) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)