Apple today seeded build 12F17 of OS X 10.8.5 to developers, offering a third version of the next Mac operating system update for testing. The release comes one week after the appearance of the previous beta of OS X 10.8.5, build 12F13.

12f17
As with previous betas, the update comes with no known issues and can be downloaded via Apple's Developer Page or through the software update tool in the Mac App Store.

Testing on OS X 10.8.5 comes as Apple is also continuing work on its next major version of OS X, Mavericks. Apple has already seeded two developer previews of OS X Mavericks and has announced that it will launch the new operating system to the public this fall.

Top Rated Comments

WildCowboy Avatar
161 months ago
Can any one explain to me why they are still doing this instead of putting extra work in Mavericks? Not that it bothers me, just asking

Mavericks isn't coming for months, and there are things in Mountain Lion that need fixing.
Score: 14 Votes (Like | Disagree)
beelzebubba Avatar
161 months ago
Can any one explain to me why they are still doing this instead of putting extra work in Mavericks? Not that it bothers me, just asking

Because many people still run ML and will even after Mavericks comes out. ML will likely be the end of the line for some older Macs and Apple has done fairly well in supporting legacy machines even past the five year end of life.
Score: 8 Votes (Like | Disagree)
laflores Avatar
161 months ago
Can any one explain to me why they are still doing this instead of putting extra work in Mavericks? Not that it bothers me, just asking

Because otherwise, people would start crying because "apple doesn't care about mountain lion any more" and some people will complain that mavericks is a piece of **** and they rather stay with snow leopard...
Score: 8 Votes (Like | Disagree)
rdlink Avatar
161 months ago
Gonna miss those cats when they're gone.
Score: 7 Votes (Like | Disagree)
iBug2 Avatar
161 months ago
(not trolling)

first time that safari has ever been snappier for me....running rMBP.....but it might also just be because safari in mavs is horrible

Are you kidding me? Safari 7.0 finally solves the memory issue which was introduced in 5.1 where when you open many tabs, web process just crashes. 7.0 does not have that, the single most annoying Safari bug in 2 years being solved finally.
Score: 5 Votes (Like | Disagree)
darkknight14 Avatar
161 months ago
Gonna miss those cats when they're gone.

Me too, every time I look at that new wave background it makes me want to go for a p***
Score: 4 Votes (Like | Disagree)

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