Windows Vista build 5212 (winmain)

Windows Vista build 5212 (winmain) is a pre-Beta 2 build of Windows Vista. This build was leaked on 2016-12-19 to BetaArchive. Aero can be enabled on this build in VMware, unlike 5112, but it looks identical to the aforementioned build.

This is the leaked winmain compile, and it's not to be confused with the vbl_ux_dev_checkin compile.

Setup
Although setup is similar to aforementioned builds of Vista, the autorun prompt upon booting into setup now fits more perfectly on the screen and is positioned correctly. Fonts used in the first page of setup also now use anti-aliasing once again.

Changes and new features

 * The watermark now states Beta 2 rather than Beta 1.
 * The Avalon/Indigo and fundamental drivers shortcuts have now been removed.
 * Upon right clicking on applications, a new "Run Elevated..." prompt will appear. This essentially runs applications under administrative privileges.
 * Option to create a list returns in this build.

Windows Media Center

 * Windows Media Center is included in this build, and it features a drastically different look compared to the one featured in Windows XP Media Center Edition 2005.
 * It is also included on the taskbar by default.

Windows Calendar

 * Windows Calendar has been added.
 * It looks so basic compared to the final version.

Windows Photo Library

 * This build also includes the earliest version of Windows Photo Gallery, called Windows Photo Library (and it's based on another Microsoft product, Microsoft Digital Image Library).
 * A wizard appears when you open the app for the first time, asking you if you want to import anything.
 * Windows Photo Library about box has a reference to Microsoft Digital Image Library in the version banner.
 * Ability to retouch photos isn't implemented in this build.

Flip3D
This is the first leaked build to introduce what was known as Flip3D. It contains similar functionality to ALT+TAB, however it now utilizes the Desktop Window Manager in this build and creates a 3D flipping effect in between all of the applications currently open, thus the name "Flip3D". Flip3D can be used via pressing WIN+SPACE, rather than WIN+TAB which was used in later builds.

Windows Sidebar
This build is the first post-reset build of Windows Vista to reintroduce Windows Sidebar. Rather than working inside explorer.exe (which caused memory leaks), this time Sidebar runs in its own process.

Gadgets are mentioned "Parts" inside the user folder. There are 4 gadgets: Clock, RSS Feed, Photo Slideshow and Search.

In this build, Sidebar wouldn't start upon startup.

Tablet PC Components
This build includes Windows Tablet PC components (Sticky Notes, Inkball and Windows Journal). Also, New section in the context menu now has an option for creating a Windows Journal file.

Bugs

 * If launching the Sidebar process and then terminating it, the watermark may not position itself correctly.
 * Apps shown on the taskbar may appear at the very end of the taskbar.
 * If recycling something or adding something to the recycle bin, the icons won't change unless you log out and log back in.