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 39a is a followup to Safari Technology Preview 39, which was released earlier this week but suffered from a crashing issue on launch on macOS High Sierra. The new update includes the same features with 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.

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.

Top Rated Comments

redheeler Avatar
99 months ago
This is how they routinely deactivate software for their "obsolete" Macs to get you to go out and buy a new one.
As someone who owns a lot of older Macs from 2010 and 2011, now six or seven years old, I am actually surprised at how well they run Apple's latest software. It's true I upgraded them with SSDs, and newer versions of MacOS kind of need that to perform well - but it's certainly not the same as going out and buying a new Mac.

10 years ago, the newest Mac OS X running flawlessly on a 7-year-old Mac (or even older, as technically unsupported Macs from 2008/2009 can run MacOS Sierra today) was almost unheard of. The dual-processor G4 towers could just barely do ok on Leopard, and without official support from Apple (733 MHz+ was required).
Score: 6 Votes (Like | Disagree)
redheeler Avatar
99 months ago
The bigger question for me is what kind of quality control does "TimMAAY" have that no one even bothered to launch the build before releasing it to the public? I realize this is a beta release, but this is ridiculously embarrassing even for that. This is something that most Alpha releases don't even do!
Obviously the crash wasn't happening for everyone. I installed Release 39 on my 5K iMac, haven't updated to 39a, and no issues whatsoever.

I'm sure it was tested before release, and it didn't crash for them either - but it's simply not possible to take into account all possible issues and testing environments. I also wonder if somehow the app got corrupted during distribution, and some users downloaded the corrupted version while others did not. Only Apple knows for sure what happened.

But this is kind of the point of beta software, to find and fix issues that might be missed during Apple's own testing. Crash reports are sent and that helps Apple locate and fix an issue that otherwise may not be easy to discover or reproduce.
Score: 5 Votes (Like | Disagree)
kevinthebright Avatar
99 months ago
You're assuming that Apple wasn't testing to see how they could deliberately MAKE it crash on certain machines. Apple does this. This is how they routinely deactivate software for their "obsolete" Macs to get you to go out and buy a new one. I see this a lot on an older Mac Pro. Apple desperately wants the Silver Tower people to give up those machines but they won't because Apple doesn't have a product that does what they will do STILL after ALL these YEARS! :(
Do you have evidence or is this just a conspiracy theory?
Score: 3 Votes (Like | Disagree)
MacSince1985 Avatar
99 months ago
You're assuming that Apple wasn't testing to see how they could deliberately MAKE it crash on certain machines. Apple does this. This is how they routinely deactivate software for their "obsolete" Macs to get you to go out and buy a new one. I see this a lot on an older Mac Pro. Apple desperately wants the Silver Tower people to give up those machines but they won't because Apple doesn't have a product that does what they will do STILL after ALL these YEARS! :(
Can you give us some evidence or examples? I have one of those silver towers (2010, upgraded to 12-core 3.46GHz) and it runs everything I throw at it smoothly.
Score: 3 Votes (Like | Disagree)
JaguarF Avatar
99 months ago
479 points on html5test. Safari is catching up.
Score: 2 Votes (Like | Disagree)
mdriftmeyer Avatar
99 months ago
You're assuming that Apple wasn't testing to see how they could deliberately MAKE it crash on certain machines. Apple does this. This is how they routinely deactivate software for their "obsolete" Macs to get you to go out and buy a new one. I see this a lot on an older Mac Pro. Apple desperately wants the Silver Tower people to give up those machines but they won't because Apple doesn't have a product that does what they will do STILL after ALL these YEARS! :(
You have never worked for an OS company. Being NeXT/Apple alum nothing we did was overseen by Steven P. Jobs. To insinuate Timmmay isn't doing his job makes you look like an imbecile. I fully expect the child police of Macrumors to warn me for calling you out, but you are an imbecile.
Score: 2 Votes (Like | Disagree)

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