# Safari Technology Preview 230 Release Notes Learn about the latest web technology updates in Safari Technology Preview: Animations, CSS, HTML, MathML, Media, Rendering, SVG, Security, Web API, Web Extension, and Web Inspector. ## Overview [Safari Technology Preview](https://webkit.org/blog/6017/introducing-safari-technology-preview/) Release 230 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: [300291@main…300986@main](https://github.com/WebKit/WebKit/compare/967b8318789f7e0dd92f68fd31d944f0609593db...a53c1df6dfa172655ffcbc1fdd2dacf6cb68fa27). ### Animations #### Resolved Issues - Fixed `animation-name` resolution to correctly find matching `@keyframes` within tree-scoped and shadow DOM contexts. ([300706@main](https://commits.webkit.org/300706@main)) (156484228) ### CSS #### Resolved Issues - Fixed incorrect handling of `auto` inline margins on grid items during track sizing that caused excessive vertical spacing in subgrids. ([300422@main](https://commits.webkit.org/300422@main)) (157638931) - Fixed CSS anchor positioning to remember the last successful position option at `ResizeObserver` delivery time, aligning with the spec. ([300890@main](https://commits.webkit.org/300890@main)) (159225250) - Fixed an issue where transitioning an element to `display: none` with `transition-behavior: allow-discrete` and CSS Anchor Positioning would repeatedly restart the transition. ([300519@main](https://commits.webkit.org/300519@main)) (160421419) - Fixed the acceptable anchor algorithm in CSS Anchor Positioning to correctly consider inline elements as containing blocks. ([300614@main](https://commits.webkit.org/300614@main)) (160917762) - Fixed CSS nesting to inline parent selectors when possible instead of always wrapping them in `:is()` to improve selector performance. ([300297@main](https://commits.webkit.org/300297@main)) (160927950) - Fixed `position-try-fallback` resolution by treating names as tree-scoped references to properly search shadow DOM host scopes. ([300333@main](https://commits.webkit.org/300333@main)) (161081231) - Fixed an issue where a `` element with long `` text caused horizontal scrolling when nested inside a flex item. ([300684@main](https://commits.webkit.org/300684@main)) (161563289) - Fixed `getComputedStyle` to return numeric values (`2`) for `orphans` and `widows` instead of the internal `auto` value, ensuring the computed values correctly reflect the CSS specification. ([300690@main](https://commits.webkit.org/300690@main)) (161566631) - Fixed `column-count: 1` so that it now correctly creates a multi-column container per the CSS Multi-column Layout specification. ([300787@main](https://commits.webkit.org/300787@main)) (161611444) - Fixed the calculation of anchor positions in `vertical-rl` multi-column layouts by correctly flipping coordinates in fragmented flows. [(300807@main)](https://commits.webkit.org/300807@main) (161616545) - Fixed the order to try anchor position fallback options, such that the last successful position option is tried first, followed by the original style, and then the remaining options. ([300909@main](https://commits.webkit.org/300909@main)) (161714637) - Fixed `position-area` handling to include the in-flow scrollable area of the initial containing block. ([300921@main](https://commits.webkit.org/300921@main)) (161741583) - Fixed `position-visibility: no-overflow` to respond correctly to scrolling. ([301211@main](https://commits.webkit.org/301211@main)) (162173481) - Fixed: Renamed `position-area` keywords from `x-self-start`, `x-self-end`, `y-self-start`, and `y-self-end` to `self-x-start`, `self-x-end`, `self-y-start`, and `self-y-end` respectively to align with updated CSSWG specifications.([301226@main](https://commits.webkit.org/301226@main)) (162214793) ### HTML #### Resolved Issues - Fixed an issue where navigating to `:~:text` fragments on dynamically generated pages did not highlight or scroll to the fragment. ([300918@main](https://commits.webkit.org/300918@main)) (150880542) ### MathML #### Resolved Issues - Fixed rendering of unknown MathML elements so they now behave like `mrow` as required by the MathML Core specification. ([300580@main](https://commits.webkit.org/300580@main)) (148593275) ### Media #### Resolved Issues - Fixed `MediaRecorder` to no longer fire erroneous error events when stopped immediately after track changes, aligning behavior with Chrome and closer to Firefox. ([300682@main](https://commits.webkit.org/300682@main)) (161124260) ### Rendering #### Resolved Issues - Fixed incorrect clipping of position:fixed/sticky content during view transitions. ([300561@main](https://commits.webkit.org/300561@main)) (154886047) - Fixed an issue that caused cropped flexbox elements to render incorrectly. ([300433@main](https://commits.webkit.org/300433@main)) (159638640) - Fixed an issue where sticky elements at the edge of the viewport could disappear during rubber band scrolling. ([300544@main](https://commits.webkit.org/300544@main)) (160385933) - Fixed flickering of elements with slow-painting content during view transitions. ([300902@main](https://commits.webkit.org/300902@main)) (160886647) - Fixed an issue where elements with both `opacity` and CSS `filter` effects could render incorrectly. ([300549@main](https://commits.webkit.org/300549@main)) (161130683) - Fixed an issue where elements with background images were not counted as contentful for Paint Timing. ([300667@main](https://commits.webkit.org/300667@main)) (161456094) ### SVG #### Resolved Issues - Fixed an issue where `stop-color` incorrectly accepted hashless hex color values like `1234` by treating them as invalid to follow the spec. ([300296@main](https://commits.webkit.org/300296@main)) (119166640) - Fixed an issue where SVG pattern `tileImage` could appear blurred or pixelated when zooming or printing. ([300357@main](https://commits.webkit.org/300357@main)) (159202567) - Fixed `SVGAElement` so that its `rel` and `relList` attributes now affect navigation behavior, including proper handling of `noopener`, `noreferrer`, and the new `opener` value, aligning SVG links with `HTMLAnchorElement` behavior. ([300462@main](https://commits.webkit.org/300462@main)) (160724516) ### Security #### Resolved Issues - Fixed parsing of `require-trusted-types-for` in CSP to ensure `'script'` is only valid when followed by whitespace or end of buffer. ([300770@main](https://commits.webkit.org/300770@main)) (147760089) ### Web API #### New Features - Added support for Largest Contentful Paint. ([300834@main](https://commits.webkit.org/300834@main)) (161705604) #### Resolved Issues - Fixed an issue where the first `pointerdown` event was lost after triggering a context menu by right-clicking. ([300696@main](https://commits.webkit.org/300696@main)) (84787733) - Fixed Trusted Types to only verify event handler attributes for elements in the XHTML, SVG, and MathML namespaces, preventing incorrect checks on other namespaces. ([300783@main](https://commits.webkit.org/300783@main)) (147763139) - Fixed an issue where `navigate.back` in the main frame would fail after a `navigate.back` in a child frame by properly clearing the provisional history item to allow correct back navigation. ([301092@main](https://commits.webkit.org/301092@main)) (158259024) - Fixed `NavigateEvent.sourceElement` to correctly reference the submitting `HTMLFormElement` instead of `null` when a form is submitted. ([301252@main](https://commits.webkit.org/301252@main)) (160391355) - Fixed `EventCounts` interface was not `maplike`. Enables use of methods such as `.forEach()`, `keys()`, and `entries()`. ([300830@main](https://commits.webkit.org/300830@main)) (160968888) - Fixed an issue where `mousemove` events were still dispatched to removed `mouseover` targets instead of their parent element when the target was deleted. ([300522@main](https://commits.webkit.org/300522@main)) (161203639) - Fixed missing `pointerenter` and `mouseenter` events when a child element moved under the mouse. ([300564@main](https://commits.webkit.org/300564@main)) (161362257) - Fixed an issue where only one CSP violation report was sent for multiple enforced `require-trusted-types-for` directives. ([300832@main](https://commits.webkit.org/300832@main)) (161740298) - Fixed Trusted Types incorrectly treating `null` or `undefined` policy return values as `null` instead of empty strings during `createHTML`, `createScript`, and `createScriptURL` operations. ([300892@main](https://commits.webkit.org/300892@main)) (161837641) ### Web Extension #### New Features - Added support for `browser.runtime.getVersion()` to retrieve the extension version from its manifest. ([300972@main](https://commits.webkit.org/300972@main)) (161742137) ### Web Inspector #### Resolved Issues - Fixed syntax highlighting for JavaScript features like template literals, private class elements, optional chaining, and others. ([300332@main](https://commits.webkit.org/300332@main)) (107619553) - Fixed an issue where navigating the DOM tree using the keyboard would get stuck in a loop within certain subtrees. ([300471@main](https://commits.webkit.org/300471@main)) (159841729) - Fixed an issue where adding DOM attributes or node siblings did not work correctly when using the actions from the context menu. ([300752@main](https://commits.webkit.org/300752@main)) (161577627) --- 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)