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

Safari Technology Preview release 39 includes fixes and improvements for Beacon API, Directory Upload, Fetch API, Input Events, JavaScript, WebAssembly, WebRTC, Web Inspector, and Media. With Safari 11 now available to developers through the macOS High Sierra beta, Apple is providing two versions of Safari Technology Preview, one for macOS Sierra users and one for those using macOS High Sierra.

Safari Technology Preview users might want to hold off on downloading Safari Technology Preview 39 as the new version appears to be crashing at launch and not working properly.

The Safari Technology Preview update is available through the Software Update mechanism in the Mac App Store 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.

Update: The Safari Technology Preview 39 release has been pulled by Apple and is no longer available for download.

Top Rated Comments

Robert.Walter Avatar
109 months ago
I installed it. And must say it was the snappiest crash ever!

(Actually did crash on install.)

Edit: I wrote crash on install but this may have been on some kind of auto start during install. I’m not sure, as I wasn’t paying attention, just noticed that the crash report dialogue box popped up.

Also, my Mac mini 2012 is running the latest High Sierra Public Beta installed on 9/1 or 9/2 and, this, I’m running STP for High Sierra.
Score: 4 Votes (Like | Disagree)
Erdbeertorte Avatar
108 months ago
Many thanks for the info!
I just told them to update the article.


Edit: Thanks @Weaselboy :) for updating it.
Score: 2 Votes (Like | Disagree)
dantracht Avatar
108 months ago
@dantracht @Vashetti @groovyd

Yes it got pulled as you can see here: https://developer.apple.com/safari/download/

Although it never showed up in the App Store for me since a few versions ago on three different Macs (two got even a few clean installs without backup import in the meanwhile). Even the High Sierra betas sometimes don't show up and I had to download the full installer.

I always check that website every day after a new High Sierra beta had been released.

On all Macs the developer beta access utility was installed.

Still no crash with 39 on my Late 2011 MBP. Didn't test it on the other two Macs yet.



On my iMac there is also still iTunes 12.7 (running fine) what I never got on the other Macs. It had been pulled months ago shortly after release and never came back.
Many thanks for the info!
Score: 1 Votes (Like | Disagree)
PsykX Avatar
109 months ago
A very snappy crash!
It was about time they made their crashes snappier!

Works totally fine on my Mac though.
Score: 1 Votes (Like | Disagree)
bradhs Avatar
109 months ago
No crashing issues here...
Score: 1 Votes (Like | Disagree)
dlbilling Avatar
109 months ago
Yes, indeed! A very snappy crash! Mine did not crash on install, just the first launch. My MacBook Air is running Sierra 10.12.6.

Is there an option to go back down to release 38?

I'm not a developer, just testing from a user perspective, and only started recently. Is there an official way we should report the problem? Although, I would hope the powers that be already know...

Is our only option to go back to Safari and just wait for another update?
Score: 1 Votes (Like | Disagree)

Popular Stories

Apple Wallet ID Illinois

Apple Plans to Expand iPhone Driver's Licenses to These 7 U.S. States

Wednesday December 24, 2025 8:40 am PST by
In select U.S. states, residents can add their driver's license or state ID to the Apple Wallet app on the iPhone and Apple Watch, and then use it to display proof of identity or age at select airports and businesses, and in select apps. The feature is currently available in 13 U.S. states and Puerto Rico, and it is expected to launch in at least seven more in the future. To set up the...
iPhone Top Left Hole Punch Face ID Feature Purple

iPhone 18 Pro Launching Next Year With These 12 New Features

Tuesday December 23, 2025 8:36 am PST by
While the iPhone 18 Pro and iPhone 18 Pro Max are not expected to launch for another nine months, there are already plenty of rumors about the devices. Below, we have recapped 12 features rumored for the iPhone 18 Pro models. The same overall design is expected, with 6.3-inch and 6.9-inch display sizes, and a "plateau" housing three rear cameras Under-screen Face ID Front camera in...
maxresdefault

Where's the New Apple TV?

Monday December 22, 2025 11:30 am PST by
Apple hasn't updated the Apple TV 4K since 2022, and 2025 was supposed to be the year that we got a refresh. There were rumors suggesting Apple would release the new Apple TV before the end of 2025, but it looks like that's not going to happen now. Subscribe to the MacRumors YouTube channel for more videos. Bloomberg's Mark Gurman said several times across 2024 and 2025 that Apple would...
maxresdefault

10 Mac Apps Worth Trying in 2026

Wednesday December 24, 2025 9:27 am PST by
2026 is almost upon us, and a new year is a good time to try out some new apps. We've rounded up 10 excellent Mac apps that are worth checking out. Subscribe to the MacRumors YouTube channel for more videos. Alt-Tab (Free) - Alt-Tab brings a Windows-style alt + tab thumbnail preview option to the Mac. You can see a full window preview of open apps and app windows. One Thing (Free) -...
iOS 26

iOS 26.2 Adds These 8 New Features to Your iPhone

Monday December 22, 2025 8:47 am PST by
Earlier this month, Apple released iOS 26.2, following more than a month of beta testing. It is a big update, with many new features and changes for iPhones. iOS 26.2 adds a Liquid Glass slider for the Lock Screen's clock, offline lyrics in Apple Music, and more. Below, we have highlighted a total of eight new features. Liquid Glass Slider on Lock Screen A new slider in the Lock...
airpods color prototypes

Apple Tested AirPods in Bright Colors

Saturday December 27, 2025 6:06 am PST by
Apple reportedly tested a version of the first-generation AirPods with bright, iPhone 5c-like colored charging cases. The images, shared by the Apple leaker and prototype collector known as "Kosutami," claim to show first-generation AirPods prototypes with pink and yellow exterior casings. The interior of the charging case and the earbuds themselves remain white. They seem close to some...
iPhone Fold Vertical Feature

Why Apple's Foldable iPhone May Be Smaller Than Expected

Tuesday December 23, 2025 5:21 am PST by
Apple's first foldable iPhone, rumored for release next year, may turn out to be smaller than most people imagine, if a recent report is anything to go by. According to The Information, the outer display on the book-style device will measure just 5.3 inches – that's smaller than the 5.4-inch screen on the ‌iPhone‌ mini, a line Apple discontinued in 2022 due to poor sales. The report has led ...
iPhone SE Cosmopolitan Clean

Apple Discontinued These 25 Products This Year

Wednesday December 24, 2025 7:24 am PST by
With the end of 2025 near, the time has come to look back at the devices and accessories that Apple discontinued throughout the year. Most of the products that were discontinued this year were simply replaced by a new model with an updated chip. However, the iPhone SE line was entirely discontinued when the iPhone 16e launched, and the iPhone Plus line is being phased out. Below, we have...
Foldable iPhone 2023 Feature Iridescent Search

Samsung Developing 'Wide Fold' With iPhone Fold-Like Design Ahead of Apple's 2026 Launch

Tuesday December 23, 2025 11:55 am PST by
Samsung is working on a new foldable smartphone that's wider and shorter than the models that it's released before, according to Korean news site ETNews. The "Wide Fold" will compete with Apple's iPhone Fold that's set to launch in September 2026. Samsung's existing Galaxy Z Fold7 display is 6.5 inches when closed, and 8 inches when open, with a 21:9 aspect ratio when folded and a 20:18...