Apple has released Safari Technology Preview 223, 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 223 includes fixes and updates for CSS, JavaScript, Rendering, SVG, Text, Web API, Web Extensions, and Web Inspector.

The current ‌Safari Technology Preview‌ release is compatible with machines running macOS Sequoia and macOS Tahoe, the newest version of macOS that’s set to launch this later this year.

Overview

Safari Technology Preview Release 223 is now available for download for macOS Tahoe and macOS Sequoia. 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: 295968@main…296486@main.

CSS

New Features

Added support for allowing declarations directly inside @scope rule without a style rule ancestor. (296262@main) (145101643)

Resolved Issues

Fixed: Apply space from align-content when grid container and rows have definite sizes during column sizing (296300@main) (85252183)

Fixed <frame> and <frameset> to always be in-flow and non-floating. (296236@main) (102670652)

Fixed style container query on :host CSS pseudo-class to be correctly applied to slotted elements. (296080@main) (147684247)

Fixed space-around and space-evenly to fallback to safe center for align-content. (296239@main) (153403381)

Fixed the serialization of <color> custom properties to provide the used value. (296337@main) (153675017)

Fixed clamping the result of progress() between 0 and 1. (296440@main) (153895964)

JavaScript

New Features

Added support for Intl.Locale.prototype.variants getter. (296467@main) (153939662)

Resolved Issues

Fixed RegExp#[Symbol.search] to throw TypeError when lastIndex isn’t writable. (296443@main) (146488846)

Fixed DateTime string parsing for ISO8601 inputs. (296339@main) (153679940)

Fixed toIntegerOrInfinity to truncate negative fractional values to +0.0. (296468@main) (153939418)

Rendering

Resolved Issues

Fixed a list-style-position: inside list item marker to be rendered as the first child of the list item. (296451@main) (79587134)

Fixed using setDragImage with a fixed-position element, so that the drag preview bitmap includes the correct content. (296117@main) (90120656)

Fixed integrating popovers with anchor positioning. (295995@main) (141094328)

Fixed box-shadow with spread on a border-radius box to scale the radii correctly. (296481@main) (149490613)

Fixed SVG transform translate(X) not equal to translate(X,0). (296008@main) (151643419)

Fixed border-image repaint code is broken in some writing modes. (296016@main) (152396671)

Fixed box-shadow to repaint correctly in vertical-rl and horizontal-bt writing modes. (295977@main) (152803240)

Fixed border to no longer be adjusted in computed style for elements with native appearance (296129@main) (153152167)

Fixed margin-trim to not trim inline margins on block-level boxes, regardless of their position. (296212@main) (153240895)

Fixed text-wrap-style to not constrain single line content. (296471@main) (153755326)

SVG

Resolved Issues

Fixed handling of auto for rx and ry on <ellipse>. (296195@main) (153274593)

Text

Resolved Issues

Fixed Korean counter styles to be aligned with manual Korean numbering in lists. (296203@main) (152969810)

Web API

Resolved Issues

Fixed the mousemove event to be fired when the mouse stays in the document but there is no element. (296341@main) (120551245)

Fixed IntersectionObvserver to notify observers asynchronously. (296279@main) (152684301)

Web Extensions

New Features

Added support for dom.openOrClosedShadowRoot() and element.openOrClosedShadowRoot. (296168@main) (153118095)

Resolved Issues

Fixed high priority redirects to supercede low priority blocks for declarativeNetRequest. (296000@main) (145241581)

Fixed CSS display: none matching everything still getting applied even after an ignore-following-rules action was matched. (296149@main) (152996225)

Fixed calling scripting.registerContentScripts() sometimes returning the error: “Error: Invalid call to scripting.registerContentScripts(). Failed to add content script.” (296093@main) (153001967)

Web Inspector

Resolved Issues

Fixed clicking on the “+” button in the Sources tab sidebar doing nothing when Web Inspector is undocked. (296458@main) (153193833)

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.

Topics Apps macOS News Safari Technology Preview