Skip to main content

Safari 26.3 includes welcome improvements for users and developers, here’s what’s new

Alongside today’s system updates, Apple has released Safari 26.3, with a mix of under-the-hood improvements and at least one major usability upgrade for Vision Pro users. Here are the details.

Better fullscreen handling on visionOS, efficiency improvements for all

With Safari 26.3, Vision Pro users on visionOS 26.3 will see Safari automatically dim their surroundings when a video enters fullscreen, a change Apple says helps “put the focus on the content.”

In addition, Safari 26.3 introduces support for Zstandard (Zstd), an open, real-time compression algorithm developed by Meta that essentially compresses text-based web assets before they’re delivered to browsers and then decompresses them quickly on-device.

Apple says that “Zstandard decompresses quickly, reducing the workload on users’ devices. It also compresses fast enough to do on-the-fly, whereas Brotli is typically pre-compressed during your build process.”

Apple notes that users need to be running Safari 26.3 on iOS 26.3, iPadOS 26.3, visionOS 26.3, and macOS Tahoe 26.3 for Zstd support to work.

If you’re a developer, you might be happy to know that Safati 26.3’s Navigation API now “exposes a AbortSignal on NavigateEvent which triggers when the navigation is aborted,” which Apple says is a “reliable way to cancel ongoing work when a navigation gets interrupted.”

Finally, WebKit for Safari 26.3 contains the following developer-facing bug fixes and improvements:

CSS

  • Fixed a style resolution loop that occurred when a position-try box was inside a display: none ancestor. (163691885)
  • Fixed an issue where anchor-positioned elements repeatedly transitioning from display: block to display: none cause position jumps during animation. (163862003)
  • Fixed an issue where fixed-positioned boxes using position-area were incorrectly included in the scrollable containing block calculation. (164017310)
  • Fixed an issue where text-decoration: underline was rendered too high when text-box-trim was applied to the root inline box. (165945326)
  • Fixed a multi-column layout issue where the widows and text-indent properties are applied cause an incorrect indent on the portion of the paragraph that flows into the next column. (165945497)
  • Fixed an issue where CSS cursors like moveall-scrollew-resize, and ns-resize did not display correctly. (166731882)

DOM

  • Fixed incorrect timestamp handling and switched to use the raw touch timestamp. (164262652)

Media

  • Fixed an issue where the fullscreen button in visionOS inline video controls did not visually indicate interactivity by extending the glow effect to all button.circular elements. (164259201)
  • Fixed Video Viewer mode for iframe videos on macOS. (164484608)
  • Fixed an issue where Safari could not play live videos when the sourceBuffer content is removed and re-added causing the seek to not complete. (165628836)

Rendering

  • Fixed an issue where positioned or transformed <img> elements containing HDR JPEGs with gain maps would incorrectly render as SDR. (163517157)

Safe Browsing

  • Fixed a bug where if Safe Browsing queried for an entry on the Public Suffix List, and a Safe Browsing vendor responded that the whole effective TLD was unsafe, the whole site would be marked as unsafe. (168155375)

To learn more about Safari 26.3, follow this link.

Accessory deals on Amazon

FTC: We use income earning auto affiliate links. More.

You’re reading 9to5Mac — experts who break news about Apple and its surrounding ecosystem, day after day. Be sure to check out our homepage for all the latest news, and follow 9to5Mac on Twitter, Facebook, and LinkedIn to stay in the loop. Don’t know where to start? Check out our exclusive stories, reviews, how-tos, and subscribe to our YouTube channel

Comments

Author

Avatar for Marcus Mendes Marcus Mendes

Marcus Mendes is a Brazilian tech podcaster and journalist who has been closely following Apple since the mid-2000s.

He began covering Apple news in Brazilian media in 2012 and later broadened his focus to the wider tech industry, hosting a daily podcast for seven years.