Apple today seeded build 12F23 of OS X 10.8.5 to developers, offering a fifth 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 12F20.
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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 three 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

macs4nw Avatar
159 months ago
The regularity of these ML seeds is reassuring, considering all the work that must be going on with iOS7 and Mavericks.
Score: 5 Votes (Like | Disagree)
nikicampos Avatar
159 months ago
I guess this will be the last update for Mountain Lion, good.

Since Snow Leopard I think OS X is not that at it's best, hopefully Mavericks will be more like Snow Leopard performance wise.
Score: 5 Votes (Like | Disagree)
dastinger Avatar
159 months ago
And why would all that come to OSX with an incremental update of an OS that will be outdated by fall?

Do you know what they will probably fail on doing? Blocking people from posting entire replies using hugely sized bold fonts on forums.
Score: 4 Votes (Like | Disagree)
Parasprite Avatar
159 months ago
I guess this will be the last update for Mountain Lion, good.

What makes you say that? Granted these aren't the days where we'd see 10.x.13, but I don't see why anything would prove us failing to see 10.8.6 in the future.
Score: 4 Votes (Like | Disagree)
RayK Avatar
159 months ago
Hopefully if this is the last version of 10.8 they release all of the new hardware BEFORE this so I don't have to support yet another OS so soon... BRING ON THE HASWELL HARDWARE!
Score: 3 Votes (Like | Disagree)
Mr. Wonderful Avatar
159 months ago
I love how people don't remember anymore how buggy and graphically slow Snow Leopard was until 10.6.4 or 10.6.5...

If you want refinement of stability, yearly major releases of an OS are not what you're looking for.
Score: 2 Votes (Like | Disagree)

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