According to Windows Latest , Microsoft is working on a Modern Standby power-saving option that is similar to the system used in the company’s consoles. The Xbox One and Xbox Series do not completely shut down, but go into a low power mode, allowing you to download / update games, and instantly start back up.
This power saving mode will appear in Windows 10X, and then in regular Windows 10, and its implementation will resemble working with a smartphone. The OS will load emails in the background, update social media feeds and update various UWP applications, for example, Outlook, OneDrive and others.
However, users only have to select the mode once. If you want to return to standard standby mode, you will need to completely reinstall the operating system.
The Windows 10X release date is slated for spring 2021. It is not yet known when Modern Standby will appear in standard Windows 10.