Apple Releases Safari Technology Preview 158 With Bug Fixes and Performance Improvements - MacRumors
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Apple Releases Safari Technology Preview 158 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 158 includes bug fixes and performance improvements for CSS, JavaScript, WebCodecs, and more.

The current ‌Safari Technology Preview‌ release is version 16.4 and is compatible with machines running macOS Ventura and macOS Monterey.

The ‌Safari Technology Preview‌ update is available through the Software Update mechanism in System Preferences or System Settings 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

nvmls Avatar
48 months ago
Almost 2023, 158 dev versions released and still no ::before & ::after support, unreal.



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Score: 5 Votes (Like | Disagree)
gugadev Avatar
48 months ago

Almost 2023, 158 dev versions released and still no ::before & ::after support, unreal.


Only animation/transition, content generation is supported since 3.0. However, I share your thoughts, there is no logic reason to not implement it.
Score: 1 Votes (Like | Disagree)
nortonandreev Avatar
48 months ago

Dumb question... if I'm running a beta OS, do I automatically have Safari Beta/Technical Preview? Or that's something I have to install separately?

And is there a big difference between the current Safari and this Beta?

Sorry for the super basic questions, I've always wondered, been too afraid to ask.
You have to install the Technical Preview separately.

There’s not such a big difference in sense of user facing features, it’s mostly targeted to web developers (but, ofc, everybody can benefit from the improvements).
Score: 1 Votes (Like | Disagree)