Release Notes for Safari Technology Preview 216

Apr 3, 2025

by Jon Davis

Safari Technology Preview Release 216 is now available for download for macOS Sequoia and macOS Sonoma. If you already have Safari Technology Preview installed, you can update it in System Settings under General → Software Update.

This release includes WebKit changes between: 291468@main…292534@main

Accessibility

Resolved Issues

  • Fixed presentational images with empty alt attributes to be ignored by assistive technology, even when additional labeling attributes are set. (292105@main) (146429365)

CSS

New Features

  • Added additional support for text-wrap-style: pretty to now adjust all lines in the text box to improve rag and hyphenation. (291750@main) (146142653)

Resolved Issues

  • Fixed buttons to not have align-items: flex-start by default. (291883@main) (146615626)

Forms

Resolved Issues

  • Fixed form associated ElementInternals always reporting a customError when using setValidity. (291878@main) (115681066)

Media

Resolved Issues

  • Fixed stale audio buffer data after seeking when playing sound through an AudioContext. (291763@main) (146057507)

Rendering

Resolved Issues

  • Fixed integrating position-area and self-alignment properties for align-self and justify-self (291606@main) (145889235)
  • Fixed will-change: view-transition-name to create a stacking context and a backdrop root. (291636@main) (146281670)
  • Fixed will-change: offset-path to create a stacking context and a containing block. (291635@main) (146292698)

Service Workers

Resolved Issues

  • Fixed Service Worker downloads being prematurely interrupted. (291712@main) (143065672)
  • Fixed the ReadableStream cancel method not getting reliably called in Service Worker. (291551@main) (144297119)

SVG

Resolved Issues

  • Fixed SVG paint server fallback handling for a non-existent URL. (291726@main) (144493507)
  • Fixed respecting the CSS image-rendering property when drawing an SVG. (292202@main) (144507619)
  • Fixed handling url(...) none to match the SVG Paint Server specification. (291770@main) (146454258)
  • Fixed ancestor bounding box for “disabled” <foreignObject> and <image>. (292411@main) (147455573)

Text

Resolved Issues

  • Fixed <b> and <strong> to use font-weight: bolder to match the Web Specification. (291855@main) (146458131)

URLs

Resolved Issues

  • Fixed percent-encoding ^ in non-opaque URL paths. (291614@main) (146233526)
  • Fixed ensuring that opaque URL paths always roundtrip. (292146@main) (146848690)
  • Fixed making URL host and hostname setters handle @ correctly. (292041@main) (146886347)
  • Fixed Windows drive letter after file:/// when parsing URLs. (292396@main) (147381130)

Web Animations

New Features

  • Added support for the Animation property overallProgress. (291764@main) (146470359)

Web API

Resolved Issues

  • Fixed: URL’s protocol setter should forbid switching non-special to special schemes. (292443@main) (82549495)
  • Fixed the ProgressEvent members loaded and total to use the double type as per a recent specification change. (292359@main) (146356214)
  • Fixed URLPattern’s hostname and port canonicalization. (292382@main) (147109380)
  • Fixed Intrinsic Sizing of SVG embedded via <embed> to be invalidated on navigation. (292267@main) (147198632)

Deprecations

  • Removed the svgDocument interface from HTMLFrameElement to align with other browsers. (291498@main) (133800070)

Web Inspector

Resolved Issues

  • Fixed to show a separate overview for each target in the Timelines tab. (292169@main) (146356054)