Previous betas brought support for Force Touch, the new Photos app for OS X, and diverse emojis. Apple tells developers to also focus on Wi-Fi captive networks, screen sharing, and Arabic and Hebrew system language.
Developers can get more details on the build at the link below or via the Mac App Store Update panel. Apple also released a new version of OS X Yosemite Recovery update which improves the reliability when restoring from a Time Machine backup. We'll let you know if we spot anything new.
Apple has also released this build as a public beta version, for those signed up for that program.
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