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
82 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
82 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
82 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
82 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
82 months ago
No crashing issues here...
Score: 1 Votes (Like | Disagree)
dlbilling Avatar
82 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)

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