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Apple today seeded build 13D43 of OS X 10.9.3 to developers, just under a week after releasing the sixth OS X beta, build 13D38, and a little over a month after the first 10.9.3 beta.
The beta is available through the Software Update mechanism in the Mac App Store as well as through the Mac Dev Center.
Apple continues to ask developers to focus on Graphics Drivers and Audio, and Safari. As was discovered with the first beta, 10.9.3 adds new support for 4K displays, offering “Retina” resolutions that improve readability along with support for 60Hz output from the Retina MacBook Pro.
