Apple today seeded build 12F36 of OS X 10.8.5 to developers, marking the ninth developer beta iteration of 10.8.5. The release comes several weeks after the previous OS X 10.8.5 beta, build 12F33. Apple also seeded build 12F35 of OS X 10.8.5 to employees two weeks ago.

12f36
As with previous betas, the update contains no known issues and can be downloaded via Apple’s Developer page or through the software update tool of the Mac App Store. Build 12F36 asks developers to test PDF viewing and accessibility, along with mobile device management and the standard graphics, Wi-Fi, and wake from sleep functionality. A new seed of Safari 6.1 is also available for developers.

Apple's OS X 10.8.5 beta is being tested alongside the next version of the operating system, OS X Mavericks. Apple has thus far seeded seven Developer Previews of Mavericks and plans to offer the new operating system to the public in the fall.

Top Rated Comments

Dulcimer Avatar
159 months ago
Really, I don't understand all these beta releases for an outgoing operating system…..

Not everyone will update to Mavericks, and there are still bugs/issues to fix in ML.
Score: 13 Votes (Like | Disagree)
chrfr Avatar
159 months ago
Not all Macs still in use will support Maverick.
System requirements for Mavericks and Mountain Lion are identical.
Score: 12 Votes (Like | Disagree)
Mike MA Avatar
159 months ago
Really, I don't understand all these beta releases for an outgoing operating system…..
Why would you not upgrade to a far superior OS? Mavericks is a quantum leap in performance.
Not all Macs still in use will support Maverick.
Score: 11 Votes (Like | Disagree)
jameslmoser Avatar
159 months ago
That doesn't mean Apple will include supported drivers for those computers

Actually thats exactly what it means... they are all apple systems, so they will include the drivers for all those systems they sold.
Score: 7 Votes (Like | Disagree)
Risco Avatar
159 months ago
Not everyone will update to Mavericks, and there are still bugs/issues to fix in ML.

Why would you not upgrade to a far superior OS? Mavericks is a quantum leap in performance.
Score: 6 Votes (Like | Disagree)
C DM Avatar
159 months ago
Not everyone will be able to or will want to spend the money on updating. Not everyone necessarily needs to (despite it potentially being newer/better). Not everyone is using a Mac in an environment where they choose what to install or update to--like a corporate environment--and a brand new version that costs money might not get installed in an environment like that for some time, while some needed security, stability, performance, and general fixes would still be more than welcome for the existing OS that is in use in those environments.
Score: 4 Votes (Like | Disagree)

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