MSPoweruser published a story that Microsoft has released Windows UI Library 2.8.
Microsoft releases Windows UI Library 2.8
Microsoft's latest WithUI 2.8 now has support for WebView2, which means you can now embed web content in native applications with Microsoft Edge. Another change is that the supported version of WinUI 2 is now Windows 10, version 1809 — Build 17763. Aside from these changes, WinUI 2.8 comes with a good set of bug fixes and improvements.