Windows Polaris

Windows Polaris is the codename of an unreleased edition of the Windows Core OS that was in development by Microsoft.

History
Build 16299.241, which identified itself as "Windows OneCore 10" for ARM32 architecture, was compiled on January 2, 2018 and then leaked on January 2, 2021. Work on Polaris was cancelled for unknown reasons, and superseded by development on Windows 10X.