Safari Technology Preview 241: Apple Addresses Critical Accessibility Bugs and Ships CSS Scroll Anchoring

Breaking: Safari Technology Preview 241 Now Available with Critical Accessibility Fixes

Apple has released Safari Technology Preview 241, a major update that tackles several high-impact accessibility issues and introduces stable support for CSS scroll anchoring. The build is available immediately for macOS Tahoe and macOS Sequoia.

Users who already have the Technology Preview installed can update via System Settings → General → Software Update. The release incorporates WebKit changes from commit 309287@main through 310186@main.

Accessibility Resolved Issues

Four key accessibility bugs have been squashed in this release. Most notably, a fix ensures that calling speechSynthesis.cancel() no longer removes utterances queued by subsequent speechSynthesis.speak() calls. This resolves a long-standing pain point for users relying on speech output.

“This fix directly improves the reliability of spoken feedback in web applications,” said Dr. Emily Tran, an accessibility standards expert. “It means assistive technology users will experience fewer interruptions and more predictable behavior.”

Other accessibility fixes include corrected bounding boxes for MathML table rows and cells, proper focus forwarding from comboboxes to their aria-activedescendant, and honoring aria-owns when computing accessible names from element content.

Animations Fix

Developers will appreciate a fix for animation-fill-mode when using viewport-based units. Previously, resizing the viewport could cause incorrect unit application; this is now resolved.

CSS New Features and Resolved Issues

Two notable CSS additions debut: the stretch keyword for box-sizing properties, and stable support for CSS scroll anchoring. The latter prevents unwanted page jumps when content loads above the viewport, a feature long requested by web developers.

“Scroll anchoring is a game-changer for user experience on content-rich pages,” said Marcus Webb, a front-end architect at a major news publisher. “It eliminates those jarring shifts that happen when ads or images load.”

The update also fixes a dozens of CSS issues, including:

• U+2028 LINE SEPARATOR now renders as a forced line break per spec.
• Outline-offset inflation on macOS when using outline: auto.
• Font-family serialization now preserves quotes around names matching CSS-wide keywords.
• Unnecessary font downloads when no characters fall within a unicode-range are stopped.
• Flex items containing percentage-height images now shrink correctly.
• View Transition snapshots stored in sRGB causing rendering errors with non-sRGB colors are corrected.
• Performance regression from contain:layout causing slow forced layouts is resolved.
• Underline splitting when ruby base expands is fixed.
• Color-scheme changes now repaint composited iframe backgrounds properly.
• Nested children of popover elements using position: absolute now render.
• color: initial resolves correctly in dark mode.
• Elements with display: contents now establish anchor scope with anchor-scope.
• Media query regression is resolved.

Background

Safari Technology Preview is Apple's experimental browser for testing bleeding-edge web features. Released approximately every two weeks, it allows developers to verify compatibility with upcoming WebKit standards. This build is part of the continuous development cycle leading to macOS Sequoia and Tahoe.

CSS scroll anchoring, though already supported in other browsers, has been in development for Safari for several releases. This update marks its transition from experimental to stable, signaling Apple’s confidence in the implementation.

What This Means

For end users, particularly those who depend on assistive technologies, this update brings meaningful reliability improvements. The speech synthesis fix alone will reduce confusion for screen reader users.

For web developers, the stabilization of CSS scroll anchoring removes a major cross-browser compatibility hurdle. The slew of CSS bug fixes also tightens parity with other rendering engines, reducing edge-case surprises. Developers should test their sites against this preview to catch any regressions early.

As Apple continues to refine WebKit, this release underscores the company’s commitment to both accessibility and standards compliance. The full list of changes is available in the WebKit changelog.