Apple Releases Safari Technology Preview 139 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 139 includes bug fixes and performance improvements for Web Inspector, CSS, Web Animations, Rendering, SVG, WebAuthn, Web API, JavaScript, Content Security Policy, Media, Service Workers, Web Extensions, and more.

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.

Top Rated Comments

velocityg4 Avatar
7 months ago
Don’t they always say performance improvements? They never say this release is going to really tax your system.
Score: 8 Votes (Like | Disagree)
now i see it Avatar
7 months ago
Over a decade of iOS Safari and it still struggles to work properly with many websites. What are they working on?
Score: 6 Votes (Like | Disagree)
Unggoy Murderer Avatar
7 months ago

Over a decade of iOS Safari and it still struggles to work properly with many websites. What are they working on?
Been using Safari as my default browser for many years and I think I've only had one issue with a strict compatibility requirement (a bank website). What struggles are you experiencing?

I'm primarily a web developer so I'm genuinely curious about your experiences.
Score: 4 Votes (Like | Disagree)
kdekorte Avatar
7 months ago

+1, I noticed the issue in 138 as well only after updating to macOS 12.2 yesterday, was fine before that.
This was my experience as well.
Score: 3 Votes (Like | Disagree)
kdekorte Avatar
7 months ago
Anyone else having the issue where normal Safari loads pages fine, but the Tech Preview stalls when loading pages?
Score: 3 Votes (Like | Disagree)
Sheepish-Lord Avatar
7 months ago

This version since the last does 120fps while macOS Monterey 12.2 (just released) still does 60fps.

Below: macOS Monterey 12.2 safari

Safari Preview 139:

You should read the *important* notes in your screenshot. Creator of blurbusters has already stated Safari has never been compatible and it literally shows that in your screenshot.
Score: 2 Votes (Like | Disagree)

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