Windows 10 build 19640

Windows 10 build 19640 is the twenty-first Insider Preview build of Manganese. This build was released to Windows Insiders in the Fast Ring on 3 June 2020. It is the fourth released build in the  branch.

Changes

 * If the users's download folder is synced to a cloud provider, it disables the option to have Storage Sense automatically clear your Downloads folder on a cycle.
 * Login logic was updated, so if the user has their PC set up so they have to type their username while logging in, typing a space at the beginning of your username will not generate an error anymore.

Bugs and quirks

 * Both the Documents and Downloads sections under privacy settings have a broken icon, and a rectangle is shown in their place.
 * Taskbar preview thumbnails do not render consistently in this build (showing a blank area).
 * Some devices may BSOD upon resuming from hibernate if booting from eMMC storage.