Windows Vista/6.0.5098.winmain beta1.050628-1740
Windows "Longhorn" build 5098 (with the buildtag of 6.0.5098.winmain beta1.050628-1740), is one of the last builds compiled before the Beta 1 stage of Windows Vista. By this point, Microsoft implemented a substantial amount of features originally slated for Windows "Longhorn", signifying the end of the Omega-13 stage.
This build includes the Windows Aero visual style, WDDM video drivers, Start menu updates, and the Games Explorer. This build notably includes the Network Computer Sharing (formerly Castle) feature. This build leaked in January 27, 2020 from Grabberslasher from his builds on his blog.