https://wccftech.com/diablo-iv-build-cdn-update-june/

From the looks of it, the very first Diablo IV client has been pushed to Blizzard’s Vendor Content Delivery Network (CDN).

As spotted by Icy Veins, a build for project “Fenris” has been shipped to the Diablo IV CDN, and as revealed by Kotaku’s Jason Schreier back in 2018, Blizzard internally uses codename “Fenris” for its new Diablo installment.