How to Get the Latest Safari Technology Preview and Explore Its New Features

If you're a web developer or tester eager to stay on the bleeding edge of Safari, the Safari Technology Preview 241 release brings critical bug fixes and new capabilities. This guide walks you through obtaining the update on macOS Tahoe or macOS Sequoia, then highlights the key changes so you can immediately test them in your projects.

What You Need

• A Mac running macOS Tahoe or macOS Sequoia
• An existing installation of Safari Technology Preview (optional – you can also install fresh)
• An active internet connection for downloading the update or installer
• Basic familiarity with macOS System Settings

Step-by-Step Guide

1. Step 1: Verify Your macOS Version

   Open About This Mac from the Apple menu. Confirm you are running macOS Tahoe or macOS Sequoia. Safari Technology Preview 241 is only compatible with these two versions, so check before proceeding.

   

2. Step 2: Download or Update Safari Technology Preview

   If you already have the Technology Preview installed, go to System Settings → General → Software Update. Click Update Now next to the Safari Technology Preview entry. For a clean install, download the latest disk image from the Apple Developer website and mount it.

3. Step 3: Install and Launch the Preview

   Double-click the installer package. Follow the on-screen instructions – you may need to enter your admin password. Once installed, open Safari Technology Preview from your Applications folder. The version number should reflect 241.

4. Step 4: Test Accessibility Improvements

   This release includes multiple fixes that enhance assistive technology support. For example, speechSynthesis.cancel() no longer removes queued speech that was added by later speechSynthesis.speak() calls. Also, MathML table rows and cells now have correct bounding boxes, and comboboxes forward focus to their aria-activedescendant properly. Verify your ARIA implementations using VoiceOver or other tools to see these corrections in action.

5. Step 5: Review Animation Changes

   One animation bug was resolved: animation-fill-mode now correctly applies viewport-based units after resizing the viewport. Previously, values like 100vw could be misapplied during animation fills. Check your CSS animations that use viewport units to confirm they behave as expected after the fix.

6. Step 6: Explore CSS Enhancements

   Two new features are now stable: the stretch keyword for the box-sizing property, and CSS scroll anchoring (which prevents unexpected page jumps when content above the viewport changes). Additionally, several CSS bugs are squashed:

   • The U+2028 LINE SEPARATOR now forces a line break as 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 only downloaded when characters in the document actually use their unicode-range, saving bandwidth.
   • A flex item containing a percentage-height image now shrinks correctly.
   • View Transition snapshots are stored in the proper color space, fixing rendering of non-sRGB colors.
   • contain: layout performance improves when all siblings create formatting contexts.
   • Underlines are no longer split when a ruby base expands from long ruby text.
   • Changing color-scheme now repaints composited iframes correctly.
   • Nested children of a popover with position: absolute render properly.
   • color: initial resolves to the correct color in dark appearance.
   • Elements with display: contents now establish the correct anchor scope when using anchor-scope.

   Test your stylesheets against these fixes, especially if you rely on color schemes, view transitions, or popover positioning.

7. Step 7: Report Any New Issues

   If you encounter regressions or unexpected behavior, use the built-in feedback tool in Safari Technology Preview (⌘⌥I or Help → Report a Bug) to send your observations directly to the WebKit team. Your reports help shape future releases.

Tips for a Smooth Experience

• Keep your regular Safari for daily use. The Technology Preview runs independently, so you can switch back if you encounter issues.
• Enable the Develop menu (Safari → Settings → Advanced → Show Develop menu) to access Web Inspector, console, and other debugging tools.
• Test across different macOS versions. If you work on both Tahoe and Sequoia, install the preview on each to confirm cross‑version compatibility.
• Use responsive design mode to test viewport‑dependent changes like the animation-fill-mode fix.
• Check the WebKit commit logs for the exact changes (included in the release notes) to understand deeper implementation details.
• Automate your tests if possible – tools like Playwright or Puppeteer can run against the Technology Preview to catch regressions early.