Apple Releases Safari Technology Preview 143 With Bug Fixes and Performance Improvements

Apple today released a new update for Safari Technology Preview, the experimental browser Apple first introduced in March 2016. Apple designed the ‌Safari Technology Preview‌ to test features that may be introduced into future release versions of Safari.

Safari Technology Preview Feature
‌Safari Technology Preview‌ release 143 includes bug fixes and performance improvements for Web Inspector, CSS Container Queries, CSS Cascade Layers, Subgrid, CSS, JavaScript, Rendering, Web Animations, SVG, Scrolling, WebAuthn, WebGL, HTML, Web API, Media, Accessibility, File System Access, and Web Extensions.

The current ‌Safari Technology Preview‌ release is built on the Safari 15.4 update and it includes Safari 15 features introduced in macOS Monterey.

The ‌Safari Technology Preview‌ update is available through the Software Update mechanism in System Preferences to anyone who has downloaded the browser. Full release notes for the update are available on the Safari Technology Preview website.

Apple's aim with ‌Safari Technology Preview‌ is to gather feedback from developers and users on its browser development process. ‌Safari Technology Preview‌ can run side-by-side with the existing Safari browser and while designed for developers, it does not require a developer account to download.

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Top Rated Comments

adamw Avatar
45 months ago
Safari bug fixes and improvements are always welcome.
Score: 2 Votes (Like | Disagree)
nortonandreev Avatar
45 months ago

It's also gives you insight to what Safari might offer in future MacOS updates. MacOS 12.3 betas offered Safari version 15.4, and the first MacOS 12.4 beta offers Safari version 15.5. I would guess the current Safari tech preview build is 15.6 now?
It’s still on 15.4. But WebKit is newer version than the one which the latest 15.5 build is based on.
Score: 1 Votes (Like | Disagree)
TracesOfArsenic Avatar
45 months ago
I look forward to the day I can use Safari for full screen streaming while using subtitles. For years the display will flicker when UI (ie subtitles) change lines. It's subtle but it's there and it drives me mental.
Score: 1 Votes (Like | Disagree)
Sheepish-Lord Avatar
45 months ago

I look forward to the day I can use Safari for full screen streaming while using subtitles. For years the display will flicker when UI (ie subtitles) change lines. It's subtle but it's there and it drives me mental.
I look forward to the day I can watch a stream and it doesn’t eat up 2GB of memory and eventually give me a memory warning error about an 1hr with nothing else open.
Score: 1 Votes (Like | Disagree)