Earlier this month, we reported that Apple has seeded a new version of Safari to Apple employees for internal testing. Now, Apple has provided that update to developers via the Developer Center.
Versions for OS X Mavericks, OS X Mountain Lion, and OS X Lion are all available, and Apple asks developers to focus on the following during their testing:
General website compatibility, Accessibility, Viewing and annotating PDFs, Login autofill, Password autofill, Setting and using break points in Web Inspector
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