Late on Monday -- and like the iOS 7 beta released earlier in the day
, arriving two weeks after the last one -- Apple has posted OS X 10.9 Mavericks
Developer Preview 3. While it is too soon to notice any significant changes or improvements, the beta is focused on compatibility and performance issues, as well as integrating the forthcoming "iCloud Keychain"
feature. The update is still dealing with a raft of known issues, including some that render it incompatible with even the last Mavericks and iOS 7 betas. Installation on production machines remains strongly discouraged.
The update, which is just over 1GB in size, doesn't support virtual machines made by VMWare Fusion, nor does Adobe's After Effects CS6 work properly. A number of functions in DP3 are not backwards compatible with previous versions -- such as new Fusion Drive volumes, screen recordings, Recovery Partition reinstalls and iCloud Keychain. The latter, an expansion of the ability to sync keychains between devices, still has a number of serious known issues.
The iCloud Keychain proposes to move the centralized storage of secure passwords, website usernames and other important data to iCloud, with entries encrypted using 256-bit AES. This enables users to take more advantage of the built-in Password Generator that creates unmemorable complex passwords for online accounts, since users don't have to remember the password itself, just the one master password that unlocks the keychain and can be used across any devices the user has.
The release notes refer to issues with QuickTime Player, Aperture, Photoshop, Maps and others. The new update does include a newer version of OpenSSH, 6.2p2, but also lists a number of odd bugs such as "the headphone port on the new 2013 MacBook Air will not operate unless headphones are present at boot" and "on some machines, frequently sleeping and waking may result in the machines restarting," indicating that the latest release is still far from being ready for public consumption. Migration from Windows is still not supported, and network migration from earlier versions of OS X requires a Migration Update (for Snow Leopard and later) that is only available from the Mac Dev Center.
The forthcoming Mavericks promises users long-requested features such as Finder Tabs and better multi-monitor support, extensive efficiency routines that should prolong battery life, improved Maps, a faster Safari, iBooks for the Mac and many other new and improved features. It is expected sometime in early autumn, though no exact date has yet been announced.