Apple Releases Safari Technology Preview 203 – Brings Bug Fixes and Performance Improvements

Apple has released Safari Technology Preview 203, the latest version of their developer preview web browser. The preview version of Apple’s popular browser offers developers and other interested users the ability to try out features that may or may not, debut in future public release versions of Safari.

‌‌Safari Technology Preview‌ 203 includes fixes and updates for Accessibility, Canvas, CSS, Editing, JavaScript, Media, Networking, Rendering, SVG, Web Apps, Web Assembly, Web Extensions, and Web Inspector.

The current ‌Safari Technology Preview‌ release is compatible with machines macOS Sonoma and the macOS Sequoia beta, the newest version of macOS that is currently in beta testing.

Overview

Safari Technology Preview Release 203 is now available for download for macOS Sequoia beta 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: 282390@main…283042@main.

Accessibility

Resolved Issues

• Fixed display: contents on tbody elements preventing table rows from being properly exposed in the accessibility tree. (282413@main) (129131780)
• Fixed the handling of ElementInternals.ariaValueNow null values so the right value is exposed to assistive technologies. (282422@main) (129218234)
• Fixed updating the accessibility tree when text underneath an aria-describedby element changes. (282430@main) (131877635)

Canvas

Resolved Issues

• Fixed CanvasRenderingContext2D globalAlpha property getting ignored for some values of globalCompositeOperation. (282995@main) (134840885)

CSS

New Features

• Added support for scrollbar-gutter. (282662@main) (111918434)
• Added support for cursor in ::marker. (282642@main) (133256523)
• Added support for ruby-overhang. (283012@main) (135058411)

Resolved Issues

• Fixed text-underline-offset to support percentages. (282611@main) (117246233)
• Fixed: Updated calc() to the most recent web standard, including support for dividing by numbers with additional units. (282580@main) (134446246)

Editing

Resolved Issues

• Fixed aligning with the standardized version of the autocorrect attribute, which does not support Email, URL, and Password fields and does not treat the empty string value in a special way. (282792@main) (101036922)
• Fixed inserting text before a <picture> element inserting the text after the element instead. (282825@main) (134378236)

JavaScript

New Features

• Added support for Iterator.prototype.constructor and Iterator.prototype[@@toStringTag]. (282687@main) (134598491)
• Added support for Iterator.from from Iterator Helpers Proposal. (283016@main) (135065388)

Resolved Issues

• Fixed: Disallow yield and await expressions in class field initializers. (282819@main) (132338331)
• Fixed Object.keys(global) including non-enumerable properties unless deleted first. (282554@main) (134121649)
• Fixed the error message of Temporal.Instant.fromEpochMilliseconds. (282587@main) (134454596)
• Fixed duration format’s nanoseconds calculation ordering. (282690@main) (134526619)
• Fixed TimeZoneAnnotation to disallow sub-minute. (282710@main) (134541964)
• Fixed: Temporal.Instant.prototype.epochMilliseconds to return a floored value. (282718@main) (134666158)

Deprecations

• Remove obsoleted Temporal.Instant API. (282400@main) (134195010)

Media

New Features

• Added support for allowing websites to override the system-default accessibility caption styling. (282568@main) (134265139)

Resolved Issues

• Fixed a bug in WebCodecs where audio and video codecs with pending work could be prematurely garbage collected. (282657@main) (134297589)

Networking

Resolved Issues

• Fixed a bug where Cross-Origin-Opener-Policy header fields in the response of iframes were not ignored, resulting in window.opener being null after multiple cross-origin navigations of the main frame. (282482@main) (132840366)

Rendering

Resolved Issues

• Fixed items that span multiple tracks with optimizations. (282464@main) (132435056)
• Fixed rendering tick marks of the range input type when the page zoom is less than 1. (282451@main) (134282707)

SVG

Resolved Issues

• Fixed an issue for getPointAtLength to throw an exception when path is empty. (282665@main) (122574451)

Web API

Resolved Issues

• Fixed: Changed click, auxclick, contextmenu, and click() to use PointerEvent. (282524@main) (71202646)
• Fixed: Aligned oncuechange event handler handling with other event handlers. (282977@main) (98254058)
• Fixed popovertarget to work on buttons in a form. (282801@main) (131042177)
• Fixed XMLSerializer.serializeToString() not serializing the children of <img> and also not closing the <img> if it has children. (282725@main) (133404338)
• Fixed: Moved onbeforeinput to GlobalEventHandlers. (282912@main) (134943272)

Web Apps

New Features

• Parse dir member of Web Application Manifest. (282761@main) (131900106)

Resolved Issues

• Fixed Web Application Manifest parsing to trim all ASCII whitespace. (282544@main) (134336817)

Web Assembly

New Features

• Added support for return_call_ref. (282853@main) (134442713)

Web Extensions

Resolved Issues

• Fixed Safari Web Extension ports to receive messages in content scripts when sent from the onConnect event listener. (283006@main) (133501214) (FB14721836)

Web Inspector

New Features

• Added support for sourcemaps to be blackboxed. (282740@main) (133731737)
• Added support for showing boundThis for arrow functions in the console. (282553@main) (134268331)

While the preview is intended for use by developers and advanced users, to provide Apple with feedback on the development of the Safari browser, it can be run side-by-side with the release version of Safari. The app doesn’t require a developer account to download and install. For more information, visit the Safari Technology Preview website.