Apple Releases Safari Technology Preview 158 With Bug Fixes and Performance Improvements - MacRumors
Skip to Content

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.

Popular Stories

Safari Technology Preview Updated Feature 1

Apple Releases Safari Technology Preview 247 With MCP Server for AI Agent Integration

Wednesday July 1, 2026 2:11 pm PDT by
Apple today released a new update for Safari Technology Preview, the experimental browser that was first introduced in March 2016. Apple designed Safari Technology Preview to allow users to test features that are planned for future release versions of the Safari browser. Safari Technology Preview 247 adds the Safari Model Context Protocol (MCP) server meant to speed up web development and...
iPhone 18 Pro Deep Red Feature

iPhone 18 Pro Launching in Two Months With These 12 New Features

Friday July 17, 2026 10:39 am PDT by
It is now mid-July, and that means the iPhone 18 Pro and iPhone 18 Pro Max are now just two months away. The devices are expected to look similar to the iPhone 17 Pro and iPhone 17 Pro Max, but there will still be many year-over-year changes, with rumored features including a smaller Dynamic Island, 5G via satellite, and more. Apple is expected to unveil the iPhone 18 Pro, iPhone 18 Pro Max, ...
iCloud General Feature Redux

Apple Raises iCloud+ Prices in 8 Countries

Friday July 17, 2026 11:56 am PDT by
Apple has increased the price of iCloud+ in Nigeria, Türkiye, Vietnam, Japan, Egypt, New Zealand, the Philippines, and Indonesia, according to an updated version of its iCloud support document. Price increases range from 11 percent to 55 percent depending on the plan and the country. Nigeria saw the biggest hike, and a 50GB plan is now ₦1,300, up from ₦900. Türkiye saw the next largest...

Top Rated Comments

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



Attachment Image
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)