# Safari Technology Preview 237 Release Notes Learn about the latest web technology updates in Safari Technology Preview: Accessibility, CSS, DOM, HTML, Networking, Rendering, SVG, Web API, Web Authentication, Web Extensions, Web Inspector, and WebRTC. ## Overview [Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 237 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: [305774@main…306595@main](https://github.com/WebKit/WebKit/compare/aaeffadb0b6313d7188ebc636446532d1d459c2b...caed0239ff1d606ff67879ac662c1ae83c4aec9a). ### Accessibility #### Resolved Issues - Fixed slot elements referenced by `aria-labelledby` to correctly use their assigned slotted content for accessible names and ignore hidden slotted nodes. ([305882@main](https://commits.webkit.org/305882@main)) (114500560) - Fixed `` element to have consistent labels between `aria-label` and `title` attributes. ([305883@main](https://commits.webkit.org/305883@main)) (127460695) - Fixed elements with `display: contents` and content in a shadow root to have their content properly read when referenced by `aria-labelledby`. ([305918@main](https://commits.webkit.org/305918@main)) (129361833) - Fixed `aria-labelledby` to use the checkbox name instead of its value when the checkbox name comes from an associated `` element. ([305894@main](https://commits.webkit.org/305894@main)) (141564913) - Fixed grid elements with child rows in a shadow root to properly work with VoiceOver. ([306159@main](https://commits.webkit.org/306159@main)) (153134654) - Fixed elements with `aria-controls` or `aria-expanded` and the `hidden` attribute to no longer appear in VoiceOver’s Form Control menu. ([305902@main](https://commits.webkit.org/305902@main)) (162783041) - Fixed `::first-letter` text not being exposed in the accessibility tree when no other text accompanies it. ([305884@main](https://commits.webkit.org/305884@main)) (168458291) ### CSS #### New Features - Added support for the `:heading` pseudo-class selector. ([306151@main](https://commits.webkit.org/306151@main)) (158759228) #### Resolved Issues - Fixed CSS rules within `@scope` not being applied to `` and `` elements. ([306129@main](https://commits.webkit.org/306129@main)) (168101378) - Fixed dynamic `flow-tolerance` changes to trigger relayout for `display: grid-lanes`. ([306093@main](https://commits.webkit.org/306093@main)) (168711707) ### DOM #### Resolved Issues - Fixed `offsetX` and `offsetY` for SVG elements to use the outermost SVG as the base for coordinate calculation. ([305993@main](https://commits.webkit.org/305993@main)) (168548585) ### HTML #### New Features - Added support for the `source` attribute on `ToggleEvent` interface. ([306152@main](https://commits.webkit.org/306152@main)) (152580641) ### Networking #### Resolved Issues - Fixed `X-Frame-Options` to only strip tab or space characters, not vertical tabs. ([306279@main](https://commits.webkit.org/306279@main)) (126915315) - Fixed range request validation to properly handle HTTP 416 (Requested Range Not Satisfiable) responses. ([305866@main](https://commits.webkit.org/305866@main)) (168487440) ### Rendering #### Resolved Issues - Fixed table rendering for rowspanned cells and bottom border color. ([306471@main](https://commits.webkit.org/306471@main)) (94163960) - Fixed `<marquee>` elements causing incorrect table width calculations. ([306059@main](https://commits.webkit.org/306059@main)) (99826593) - Fixed table layout to properly handle `visibility: collapse` on columns. ([305997@main](https://commits.webkit.org/305997@main)) (168556786) - Fixed intrinsic sizing for absolutely positioned replaced elements. ([306309@main](https://commits.webkit.org/306309@main)) (168815514) - Fixed percentage padding in table cells to resolve against column widths. ([306281@main](https://commits.webkit.org/306281@main)) (168940907) - Fixed table height distribution to apply to tbody sections instead of only the first section. ([306457@main](https://commits.webkit.org/306457@main)) (169154677) ### SVG #### New Features - Added support for the `color-interpolation` attribute for SVG gradients. ([305921@main](https://commits.webkit.org/305921@main)) (87294645) #### Resolved Issues - Fixed `:visited` link color to properly propagate to SVG through `currentColor`. ([306387@main](https://commits.webkit.org/306387@main)) (98776770) - Fixed removing an item from `SVGTransformList` to properly allow attribute removal. ([306162@main](https://commits.webkit.org/306162@main)) (117840533) ### Web API #### New Features - Added support for async iteration over `ReadableStream` objects using `for await...of` loops. ([305808@main](https://commits.webkit.org/305808@main)) (168049382) - Added support for the Service Worker static routing Resource Timing API. ([306006@main](https://commits.webkit.org/306006@main)) (168499249) - Added `srgb-linear` and `display-p3-linear` to `PredefinedColorSpace`. ([306563@main](https://commits.webkit.org/306563@main)) (169340732) #### Resolved Issues - Fixed Content Security Policy to only recognize ASCII whitespace excluding vertical tabs to align with the specification. ([306222@main](https://commits.webkit.org/306222@main)) (108559413) - Fixed emoji input on Google Docs and similar web applications by supressing keypress events for supplementary characters. ([305914@main](https://commits.webkit.org/305914@main)) (122678873) - Fixed an issue where selecting credentials in the Digital Credentials API sometimes required a second click to trigger verification. ([305868@main](https://commits.webkit.org/305868@main)) (163295172) - Fixed window bar visibility properties (`toolbar.visible`, `statusbar.visible`, `menubar.visible`) to return static values per the HTML specification for privacy and interoperability. ([306391@main](https://commits.webkit.org/306391@main)) (166554327) - Fixed `layerX` and `layerY` to return correct values with CSS transforms. ([306300@main](https://commits.webkit.org/306300@main)) (168968832) ### Web Authentication #### Resolved Issues - Fixed an issue in Safari Technology Preview where WebAuthn authentication over NFC failed. ([306280@main](https://commits.webkit.org/306280@main)) (168456474) ### Web Extensions #### New Features - Added support for `runtime.getDocumentId()` web extension API. ([305912@main](https://commits.webkit.org/305912@main)) (168060269) ### Web Inspector #### New Features - Added support to show each individual request when there are redirects in the Network tab. ([306537@main](https://commits.webkit.org/306537@main)) (152606018) #### Resolved Issues - Fixed an issue where a large number of search results in the Search tab would freeze Web Inspector. ([306429@main](https://commits.webkit.org/306429@main)) (49234522) ### WebRTC #### New Features - Added support for the `targetLatency` attribute in WebRTC. ([306062@main](https://commits.webkit.org/306062@main)) (168225793) --- 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)