Apple Releases Safari Technology Preview 143 With Bug Fixes and Performance Improvements - MacRumors
Skip to Content

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

by

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.

Tag: Safari Technology Preview

Popular Stories

Safari Technology Preview Updated Feature 1

Apple Releases Safari Technology Preview 241 With Bug Fixes and Performance Improvements

Wednesday April 8, 2026 3:05 pm PDT by
Apple today released a new update for Safari Technology Preview, the experimental browser that was first introduced in March 2016 and just marked its tenth anniversary. 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 241 includes fixes and updates for Accessibility,...
Read Full Article • 5 comments
M5 Vision Pro Thumb 2

Apple Has Given Up on the Vision Pro After M5 Refresh Flop

Wednesday April 29, 2026 11:31 am PDT by
Apple has all but given up on the Vision Pro after the M5 model failed to revitalize interest in the device, MacRumors has learned. Apple updated the Vision Pro with a faster M5 chip and a more comfortable band in October 2025, but there were no other hardware changes, and consumers still weren't interested. The Vision Pro has been criticized for its high price tag and its uncomfortable...
Read Full Article • 699 comments
Four iPhone 18 Pro Colors Mock Feature

iPhone 18 Pro to Launch in September With These 10 New Features

Tuesday April 28, 2026 9:35 am PDT by
While the iPhone 18 Pro and iPhone 18 Pro Max are not launching until September, there are already plenty of rumors about the devices. It was initially reported that the iPhone 18 Pro models would have fully under-screen Face ID, with only a front camera visible in the top-left corner of the screen. However, the latest rumors indicate that only one Face ID component will be moved under the...
Read Full Article

Top Rated Comments

adamw Avatar
adamw
53 months ago
Safari bug fixes and improvements are always welcome.
Score: 2 Votes (Like | Disagree)
S
Sheepish-Lord
53 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)
nortonandreev Avatar
nortonandreev
53 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
TracesOfArsenic
53 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)
Read All Comments