Apple Releases Safari Technology Preview 186 – Brings Bug Fixes and Performance Improvements

Apple has released Safari Technology Preview 186, 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 186 includes fixes and updates for CSS, Forms, HTML, JavaScript, Rendering, Service Workers, Web Animations, and Web API.

The current ‌Safari Technology Preview‌ release is compatible with machines running macOS Ventura and macOS Sonoma.

Overview

Safari Technology Preview Release 186 is now available for download for macOS Sonoma and macOS Ventura. 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: 271832@main…272448@main.

CSS

New Features

• Added support for invalidating :any-link, :link, and :-webkit-any-link inside :has() (271919@main) (116616425)
• Added support for @scope invalidation. (271897@main) (119313058)
• Added support for an implicit scoping root when there is no <scope-start>. (272390@main) (119659940)
• Added support for :scope inside @scope prelude. (272065@main) (119661541)
• Added support for align-content on table cells. (272373@main) (119701629)
• Added support for content-visibility to be animate-able. (272364@main) (119940258)

Resolved Issues

• Fixed querySelector() to not throw an exception for -webkit- prefixed pseudo-elements. (272337@main) (99299129)
• Fixed :user-invalid triggering while typing a date. (272346@main) (110687369)
• Fixed nested @supports queries with declarations. (271989@main) (113652033)
• Fixed contain: inline-size breaking grid-template-rows: auto. (272085@main) (113915953)
• Fixed parsing and serialization of -webkit- prefixed pseudo-elements. (272411@main) (118081134)
• Fixed incorrect scoping roots with nested @scope. (271941@main) (119511916)
• Fixed @scope prelude to take nesting into account. (272117@main) (119711922)
• Fixed grid with size containment and min-height not sizing row correctly. (272276@main) (119736473)
• Fixed @scope to be able to have orphaned declarations with an implicit enclosing style rule. (119937025)

Forms

New Features

• Added focus ring support for <input type="checkbox" switch>. (271884@main) (119499785)
• Added vertical rendering support for <input type="checkbox" switch>. (272405@main) (119940157)

HTML

Resolved Issues

• Fixed missing support for the direction attribute in the list of attributes whose values are matched case-insensitively with attribute selectors. (272219@main) (119432066)

JavaScript

Resolved Issues

• Fixed async functions and generators to properly handle promises with throwing “constructor” getter. (272291@main) (119734587)

Rendering

Resolved Issues

• Fixed rendering for a <div> within a transformed parent <div> with overflow: hidden. (271894@main) (118901069)
• Fixed offsetHeight and offsetWidth are 0 for an inline box wrapping a block. (272386@main) (119955792)

Service Workers

Resolved Issues

• Fixed duplicate load requests with an active service worker. (272024@main) (104377727)

Web Animations

Resolved Issues

• Fixed percentage transform animations when width and height are animated. (272022@main) (63309680)
• Fixed a paused animation where currentTime is changed to 0 not restarting when unpaused. (271872@main) (118826588)

Web API

New Features

• Added a “gamepad” permission policy defaulting to * for the allow list. (272199@main) (83219098)
• Added ShadowRoot clonable attribute. (272096@main) (119707278)

Resolved Issues

• Fixed invalid coordinates on wheel and gesturechange events inside an iframe. (272176@main) (105243167) (FB11986074)
• Fixed HTMLAreaElement to align with the HTML Standard. (272217@main) (110028213)
• Fixed Scroll To Text Fragment to not scroll after dynamic stylesheet loads and the user has scrolled. (272151@main) (112608578)
• Fixed toggling the spellcheck attribute not toggling spelling markers on input elements. (271927@main) (119269616)

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.