Microsoft is rolling out Windows 10 20H1 Build 18945 to Windows Insiders in the Fast ring to include lots of new features such as WSL2 goodies, a new Cortana Beta experience, accessibility improvements, and File Explorer search improvements. Windows Defender is being rebranded to Microsoft Defender. The phone screen mirroring feature has now been expanded to work with more devices. Windows 10 programs can now connect to Linux servers via the localhost (127.0.0) address. Linux servers can now be connected to by Windows 10 apps.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-insider-build-18945-brings-a-new-cortana-experience/