Safari Technology Preview 241: Key Updates and Bug Fixes

Safari Technology Preview Release 241 is now available for download on macOS Tahoe and macOS Sequoia. Existing users can update via System Settings → General → Software Update. This build incorporates WebKit changes spanning from revision 309287 to 310186, bringing a host of improvements in accessibility, animations, and CSS handling. Below, we break down the most notable fixes and new features.

Accessibility Fixes

Several critical issues in assistive technology interactions have been resolved in this update:

• Speech synthesis cancelation: Previously, calling speechSynthesis.cancel() would inadvertently remove utterances queued by subsequent speechSynthesis.speak() calls. This has been fixed so that cancelation only affects pending utterances from the same speak request. (309349@main)
• MathML table bounding boxes: Incorrect bounding boxes computed for MathML table rows and cells could cause misalignment in screen readers. The issue is now resolved. (309640@main)
• Combobox focus forwarding: Comboboxes no longer fail to forward focus to their aria-activedescendant, enabling assistive technologies to properly highlight list items. (309641@main)
• ARIA owns attribute: The aria-owns attribute is now correctly respected when computing accessible names from element content, improving labeling accuracy. (310020@main)

Animation Improvements

One key animation bug was addressed:

• Viewport-based units in animation-fill-mode: The animation-fill-mode property now correctly applies viewport-based units after the viewport is resized, preventing visual glitches during responsive layouts. (310007@main)

CSS Enhancements

New Features

Two major CSS capabilities have been introduced:

• Stretch keyword for box sizing: The stretch keyword is now supported in box sizing properties (e.g., width: stretch), allowing elements to fill available space more intuitively. (309405@main)
• Stable CSS scroll anchoring: Scroll anchoring has been stabilized to prevent unwanted page jumps when content loads above the viewport. (310113@main)

Bug Fixes

A wide range of CSS issues have been resolved, enhancing rendering accuracy and performance:

• Line separator rendering: U+2028 LINE SEPARATOR now renders as a forced line break per the CSS specification. (309701@main)
• Outline offset inflation: The outline-offset property no longer inflates when using outline: auto on macOS. (309812@main)
• Font-family serialization: Quotes around family names that match CSS-wide keywords or generic families (e.g., 'inherit') are now preserved during serialization. (309959@main)
• Unnecessary font downloads: Fonts specified with a unicode-range that does not cover any characters in the document are no longer downloaded. (309360@main)
• Percentage-height images in flex items: A flex item containing a percentage-height image now shrinks correctly around the image. (309544@main)
• View Transition snapshots color space: Snapshots are no longer incorrectly stored in sRGB, fixing rendering issues with non-sRGB colors. (310012@main)
• Forced layout performance: Using contain: layout no longer causes significantly slower forced layouts when all siblings create their own formatting context. (310173@main)
• Ruby underlines: Underlines are no longer split when a ruby base expands due to long ruby text. (309356@main)
• Color-scheme repainting: Changing the color-scheme property now correctly repaints the background of composited iframes. (309567@main)
• Popover positioning: Nested children of a popover element with position: absolute now render properly. (310019@main)
• Color: initial in dark mode: The color: initial keyword now resolves to the correct color in dark appearance mode. (309430@main)
• Anchor-scope with display: contents: An element with display: contents now correctly establishes an anchor scope when using anchor-scope. (309946@main)
• Media query regression: A regression where media queries could fail to resolve correctly has been fixed. (Reference not provided in original)

This release also includes under-the-hood improvements for stability and compatibility. For a complete list of changes, refer to the official WebKit commit log. Download Safari Technology Preview 241 today to experience these updates firsthand.