Windows Longhorn/6.0.4089.private lab06 dev ux.040721-1800

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Build 4089 displaying the Windows Movie Maker application

Windows Longhorn build 4089.private_lab06_dev_ux.040721-1800 is a Milestone 7 build of the Windows Longhorn operating system developed by Microsoft.

Only one screenshot of this build has been released, which shows a prototype version of Windows Movie Maker 3.0 based on the Windows Presentation Foundation (then codenamed Avalon).