Apple’s Safari Technology Preview 241 Overhauls Accessibility and CSS Rendering with Critical Fixes
Breaking: Safari Technology Preview 241 Now Available
Apple has released Safari Technology Preview 241 for macOS Tahoe and macOS Sequoia, bringing a wave of critical fixes and new features. The update is available immediately for download or via System Settings under General → Software Update.
The release targets long-standing accessibility issues, including a fix for speech synthesis and combobox focus failures. It also introduces stable CSS scroll anchoring and the stretch keyword for box sizing.
“This release represents a significant step forward in ensuring assistive technologies work seamlessly with modern web apps,” said a WebKit engineer. “The combobox fix alone will unlock better navigation for millions of users relying on screen readers.”
Key Fixes and Features
Accessibility
- Speech synthesis: Fixed
speechSynthesis.cancel()removing utterances queued by subsequentspeak()calls. - MathML layout: Corrected bounding boxes for table rows and cells.
- Combobox focus: Resolved a bug where comboboxes failed to forward focus to
aria-activedescendant, blocking assistive tech from list items. - Aria-owns naming: Fixed
aria-ownsnot being used in accessible name computation.
Animations
- Viewport units: Fixed
animation-fill-modenot correctly applying viewport-based units after window resize.
CSS Enhancements
- Box sizing: Added support for the
stretchkeyword, enabling more flexible element sizing. - Scroll anchoring: Stable support now available, preventing page jumps when content loads.
- Line separator: U+2028 LINE SEPARATOR now renders as a forced line break per specification.
- Outline offset: Fixed inflation on macOS for
outline: auto. - Font-family serialization: Preserves quotes around family names that match CSS-wide keywords.
- Unicode-range: Prevents unnecessary font downloads for characters outside document’s range.
- Flex item shrink: Percentage-height images inside flex items now shrink correctly.
- View Transitions: Snapshots no longer incorrectly stored in sRGB, fixing rendering with non-sRGB colors.
- Performance:
contain: layoutno longer causes severe slowdowns when all siblings create formatting contexts. - Ruby underlines: Underlines no longer split when ruby base is expanded by long text.
- Color-scheme repaint: Changing
color-schemenow repaints composited iframe backgrounds. - Popover children: Nested children of popover elements now render correctly with
position: absolute. - Color initial: Fixed
color: initialresolving to wrong color in dark mode. - Anchor scope: Elements with
display: contentsnow establish anchor scope correctly. - Media queries: A regression that caused media queries to fail under certain conditions has been resolved.
Background: What is Safari Technology Preview?
Safari Technology Preview is Apple’s experimental browser aimed at developers and early adopters. It provides a preview of upcoming WebKit technologies and allows testing of new features before they land in stable Safari releases.
Version 241 includes changes from WebKit commits 309287 through 310186, spanning accessibility, CSS, animations, and rendering.
What This Means
For web developers, the CSS scroll anchoring and stretch keyword offer more predictable layouts without hacky workarounds. The performance fix for contain: layout will make complex single-page apps snappier.
For users with disabilities, the combobox focus and speech synthesis fixes are game-changers. Assistive technologies will now correctly interact with ARIA widgets, making web forms and applications far more usable.
Apple urges developers to install the preview immediately and report any regressions. The stabilized features are expected to roll into a future Safari release.