Apple today seeded the third beta of an upcoming macOS High Sierra 10.13.3 update to developers, two weeks after seeding the second beta and a month after releasing macOS High Sierra 10.13.2, the second major update to the macOS High Sierra operating system.

The macOS High Sierra 10.13.3 beta can be downloaded from the Apple Developer Center or through the Software Update mechanism in the Mac App Store with the proper profile installed.

macoshighsierra10133beta
It's not yet clear what improvements the third update to macOS High Sierra will bring, but it's likely to include bug fixes and performance improvements for issues that weren't addressed in macOS High Sierra 10.13.2.

No major outward-facing changes were discovered in the first two betas of macOS High Sierra 10.13.3, but we'll update this post should new features be found in the third beta.

The previous macOS High Sierra 10.13.2 update focused solely on security fixes and performance improvements, with no new features introduced.

Update: Apple has also made a public beta available for public beta testers.

Related Forum: macOS High Sierra

Top Rated Comments

justperry Avatar
101 months ago
Will this make your Mac 5%-30% slower.:rolleyes:


*I look at you Intel.:mad:
Score: 4 Votes (Like | Disagree)
RazorD Avatar
101 months ago
Will this make your Mac 5%-30% slower.:rolleyes:
No. That was already patched in 10.13.2. Have you noticed any performance changes since you installed it? :P
Score: 3 Votes (Like | Disagree)
tywebb13 Avatar
101 months ago
Anyone know which folder it downloads the installer to??
When you start the update there will be a numbered folder in /Library/Updates. The update files are inside the numbered folder.

What that number is depends on the version you get.

If you get the normal delta it will be 091-57950 (this is the only one with the new Mac OS Brain)

If you get the patch it will be 091-57567

If you get the combo it will be 091-57566

In the case that you get the 091-57950 and also require a Bridge OS, you will get another one with number 091-57951 with the separate Bridge OS Update.
Score: 1 Votes (Like | Disagree)
RazorD Avatar
101 months ago
Do you have any evidence? :eek:
Yeh. Apple's fix is called "Double Map".

https://twitter.com/aionescu/status/948609809540046849
Score: 1 Votes (Like | Disagree)
justperry Avatar
101 months ago
Well, if it was really already patched in MacOS I didn't even notice performance drops, so there's that.
Score: 1 Votes (Like | Disagree)

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