Microsoft released the .Net Core 3.0 framework today. Along with a lot of other changes, the biggest news is support for desktop app development, by supporting winforms and WPF. Venturebeat has more info on the release: https://venturebeat.com/2019/09/23/microsoft-releases-net-core-3-0-with-support-for-wpf-and-windows-forms/
And Microsoft has the announcement on their developer blog here: https://devblogs.microsoft.com/dotnet/announcing-net-core-3-0/