Safari Technology Preview 241: Key Updates and Fixes

Welcome to Safari Technology Preview 241, the latest experimental release for macOS Tahoe and macOS Sequoia. This update introduces several improvements in accessibility, animations, and CSS, along with critical bug fixes. If you already have Safari Technology Preview installed, you can update via System Settings under General → Software Update. Below, we answer common questions about the changes in this release.

1. What accessibility improvements are included in this release?

This update resolves four key accessibility issues. First, calling speechSynthesis.cancel() no longer removes utterances queued by subsequent speechSynthesis.speak() calls, ensuring better speech synthesis control. Second, incorrect bounding boxes for MathML table rows and cells have been fixed, improving screen reader accuracy. Third, comboboxes now correctly forward focus to their aria-activedescendant, allowing assistive technologies to interact with list items. Finally, the aria-owns attribute is now respected when computing accessible names from element content. These fixes enhance compatibility for users relying on assistive tools.

2. What CSS new features have been introduced?

Two notable CSS features debut in this release. The stretch keyword is now supported in box sizing properties, offering more flexible layout options. Additionally, stable support for CSS scroll anchoring has been added, preventing unwanted page jumps when content loads above the viewport. These features give developers greater control over page layout and user experience. For more on related CSS improvements, see CSS resolved issues.

3. How has animation-fill-mode been improved?

A bug in animation-fill-mode has been fixed where viewport-based units were not correctly applied after resizing the window. This issue could cause animations to behave unexpectedly, especially in responsive designs. With the fix, animations now properly adapt to viewport changes, ensuring consistent visual behavior across different screen sizes and during resizing events.

4. What are the key CSS bug fixes in this update?

Over a dozen CSS issues have been resolved. Key fixes include: the LINE SEPARATOR character (U+2028) now renders as a forced line break per spec; outline-offset is no longer inflated for outline: auto on macOS; font-family serialization preserves quotes for names matching CSS-wide keywords or generic families; fonts are no longer downloaded if no characters match their unicode-range; flex items with percentage-height images shrink correctly; View Transition snapshots avoid sRGB rendering issues; contain: layout performance improves; underlines split correctly when ruby bases expand; color-scheme changes repaint composited iframes; nested children of popover elements with position: absolute render properly; color: initial resolves correctly in dark mode; elements with display: contents establish anchor scope in anchor-scope; and media query regression is fixed. These improvements enhance layout, rendering, and compatibility.

5. Was there a fix for View Transitions?

Yes, an important bug was resolved where View Transition snapshots were incorrectly stored in sRGB, causing rendering issues with non-sRGB colors. This fix ensures that color accuracy is maintained during View Transitions, particularly with wide-gamut or color-managed content. Developers using CSS View Transitions can now expect more reliable color reproduction across different display profiles.

6. What changed related to fonts and typography?

Two font-related issues were addressed. First, font-family serialization now preserves quotes around family names that match CSS-wide keywords or generic families (e.g., "serif" vs. serif as a keyword). Second, a problem where a font was downloaded despite no characters in the document falling within its unicode-range was fixed, reducing unnecessary network requests and improving performance. Additionally, underline splitting when a ruby base expands due to long ruby text was corrected, improving East Asian typography.

7. How can I get Safari Technology Preview 241?

You can download Safari Technology Preview 241 for macOS Tahoe and macOS Sequoia from the official Apple website. If you already have a previous version installed, update directly via System Settings → General → Software Update. This release includes WebKit changes from revision 309287 to 310186, covering all the fixes and features described above. Stay tuned for future previews to keep your development environment up to date.