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Safari Technology Preview 212 Release Notes

Learn about the latest web technology updates in Safari Technology Preview: Authentication, Canvas, CSS, Forms, JavaScript, Loading, Networking, SVG, Text, Web API, and Web Inspector.

Overview

Safari Technology Preview Release 212 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: 287863@main…288540@main.

Authentication

New Features

  • Added support for setting a pin on a security key when a registration requires it. (288259@main) (122660610)

Canvas

Deprecations

  • Removed non-standard legacy alias of Canvas Compositing including setAlpha and setCompositeOperation. (287871@main) (141510218)

CSS

New Features

  • Added support for view-transition-name: match-element. (288102@main) (138932551)

Resolved Issues

  • Fixed CSSPageRule to derive from CSSGroupingRule. (288443@main) (69847560)

  • Fixed animation-name set from the view transitions dynamic UA stylesheet having extra quotes. (288417@main) (142298840)

  • Fixed the serialization and parsing of animation-name strings. (288404@main) (142318879)

Deprecations

  • Removed the non-standard CSSUnknownRule interface. (288453@main) (142380626)

Forms

Resolved Issues

  • Fixed the hover state getting lost when moving from a checkbox input to the parent label. (288449@main) (107220591)

JavaScript

New Features

  • Added support for an in-place interpreter for Wasm. (288385@main) (113768719)

  • Updated JSON.parse to provide the reviver function access to the input source text and extended JSON.stringify behavior to support object placeholders. (288223@main) (131579181)

Resolved Issues

  • Fixed calendar canonicalization logic in DateTimeFormat. (288143@main) (141792829)

  • Fixed broken output for Intl.DurationFormat digital style when hoursDisplay is "auto". (288277@main) (141969050)

  • Fixed Intl.DurationFormat to print a negative sign for minutes after hidden hours. (288317@main) (142119353)

  • Fixed Array.prototype.toReversed to fill holes with undefined. (288339@main) (142197604)

Loading

Resolved Issues

  • Fixed javascript: URL navigation to another browsing context created from window.open not checking the source’s Content Security Policy. (137941234)

Networking

New Features

  • Added support for cookies’ Partitioned attribute (opt-in partitioned cookies). (288413@main) (142317056)

PDF

Resolved Issues

  • Fixed main frame PDFs served with a CSP sandbox header not loading. (288060@main) (141166987)

Rendering

Resolved Issues

  • Fixed handling inline-box trailing content. (288082@main) (112409103)

  • Fixed grid layout animation performance by caching intrinsic logical heights during the first row sizing pass, improving efficiency and preventing invalidation issues with complex grid configurations. (287890@main) (135791322)

  • Fixed incorrect horizontal writing mode state when nested in a vertical block container. (287877@main) (141543326)

  • Fixed baseline calculation few cases for tables with empty rows. (288314@main) (142046863)

  • Fixed to refuse to break inside replaced content. (288354@main) (142224455)

SVG

New Features

  • Added support for the lh length type. (288448@main) (142068343)

Resolved Issues

  • Fixed synthesizing a viewBox in <img> only for the document element <svg>. (288134@main) (141733733)

Deprecations

  • Removed SVGDocument alias to XMLDocument. (288135@main) (123121696)

Text

Resolved Issues

  • Fixed bold synthesis to be less aggressive. (288130@main) (138047199)

Web API

New Features

  • Added support for element.focus({ focusVisible: true }). (287959@main) (97021844)

Web Inspector

New Features

  • Exposed cookie Partition Key in Web Inspector. (288103@main) (136293236)

See Also

2025