Mac OS X Public Beta build 1H39

Mac OS X Public Beta build 1H39 is the official beta release of Mac OS X Public Beta. This version was released to the public on 2000-09-13 and allowed testers to try the new operating system and Aqua interface before the official release of Mac OS X 10.0. Mac OS X Public Beta initially retailed for $29.95 in the US. It is also one of the very few macOS builds to have a timebomb.

Differences from Developer Preview 4
This build contains a few notable changes from the previous release, Developer Preview 4:
 * Setup has been heavily revamped, and now resemble the final Cheetah release. Despite that, the old Setup Assistant is still run after setup.
 * The flag next to the "Help" on the menu bar has been removed.
 * More applications have been placed onto the Dock by default. Alongside, Dock magnification is disabled by default again.
 * The menu bar has a new "Window" section after the "Special" and before the "Help".
 * The old Mac OS X Server 1.x design in "About Program" dialogs has been changed to resemble the Cheetah release.