A curious filing in Apple's bug reporting system includes a build number that suggests pre-release testing on OS X 10.9 has been much more extensive than with last year's OS X 10.8 Mountain Lion.



From Apple Insider:

The details come from a Webkit bug report submitted through Apple's own Radar system, first noticed by AppleInsider reader Tom. The filing references an operating system build number of 13A451, with the first three characters suggesting the software is OS X 10.9, and the latest three digits referring to the internal build number.

Those last three digits — "451" — imply that Apple's number of private test builds of OS X 10.9 have achieved a relatively high amount for an upcoming operating system.

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