Apple Seeds Third Beta of macOS High Sierra to Public Beta Testers - MacRumors
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Apple Seeds Third Beta of macOS High Sierra to Public Beta Testers

Apple today seeded the third public beta of an upcoming macOS High Sierra update to public beta testers, two weeks after releasing the second public beta. The third public beta of macOS High Sierra is likely identical the fourth developer beta, which was provided to developers earlier this week.

Beta testers who have signed up for Apple's beta testing program are able to download the third macOS High Sierra beta through the Software Update mechanism in the Mac App Store after the proper profile has been installed.

macos hs beta
Those who want to be a part of Apple's beta testing program can sign up to participate through the beta testing website, which gives users access to iOS, macOS, and tvOS betas. For instructions on how to install the public beta, check out our how to, and make sure to make a backup before giving the software a try. Don't install the beta on a main machine, as betas are notoriously unstable. High Sierra runs on all machines that support Sierra.

The macOS High Sierra update is designed to improve and refine the existing macOS Sierra operating system. Along with a new, more efficient file system (APFS) designed for modern storage, the update introduces Metal 2, the next-generation version of Apple's Metal graphics API with support for machine learning, external GPUs, and VR content creation.


High Efficiency Video Encoding (HEVC aka H.265) is coming in High Sierra, and many of the existing apps are being updated. Photos features a new persistent side view and editing tools for Curves, Selective Color, and Live Photos, while Siri is gaining a more natural voice and support for more music-related commands.

Safari offers a new autoplay blocking feature for videos and Intelligent Tracking Prevention to protect your privacy, while Mail storage is being optimized to take up 35 percent less space. iMessages can now be stored in iCloud, and there are new iCloud Drive file sharing options and new iCloud storage family plans.

For a full overview of the new features you can expect to see when macOS High Sierra is released in the fall, make sure to check out our macOS High Sierra roundup.

Related Forum: macOS High Sierra

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Top Rated Comments

Crazy Badger Avatar
113 months ago
Updated without any issues, but it's too slow to test anything at the minute. Will let Spotlight do it's stuff and play tomorrow, although I did notice iTunes 12.6.2 downloaded with it and that crashes when opening.

I'd be expecting another 2-4 PB's before we're getting close to a GM.
Score: 2 Votes (Like | Disagree)
jonwatso Avatar
113 months ago
If there are any testers reading this comment; is it close to being released to the public yet?
It runs pretty well, there is the occasional bug but other than that I using it on my daily Mac and I have no issues.
Score: 2 Votes (Like | Disagree)
Lycanthrope Avatar
113 months ago
Sincerely hope this is an improvement on beta 2! Machine has been running like an oven the last couple of weeks...
Score: 2 Votes (Like | Disagree)
KHock Avatar
113 months ago
Finally! They fixed the sleep issue at least me with 2010 Macbook Pro! No more overheating and dying while sleeping.
Score: 1 Votes (Like | Disagree)
LarryJoe33 Avatar
113 months ago
Yes, it comes up immediately
Score: 1 Votes (Like | Disagree)
CRaSHeR36 Avatar
113 months ago
Can anyone confirm that Amazon Prime Video won't work in Safari?
It's working for me here on a 13" MacBook Pro Late 2013 with PB3.
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Have to ask, how is Office 365 running on PB3? I have not taken the plunge yet, but I am eager to get onto High Sierra.
I'm on the Office 365 Beta Fast ring and have not had any issues with Office suite including Outlook.
Score: 1 Votes (Like | Disagree)