Windows Vista build 5212 (vbl ux dev checkin)

Windows Vista build 5212 (with a build tag of 5212.vbl.ux.dev.checkin.050808-1730) is a pre-Beta 2 build of the Microsoft Windows Vista operating system.

This build notably features a different Start button, that has been changed to an orb, similarly to how the 'Start' text was absent in x86 Longhorn builds with the Slate theme if the sidebar was enabled. This orb would not make it into winmain until 5252 however.