Additional Platforms supported .NET Core 3.1 WPF .NET 5 WPF Support for the following platforms has been removed. Silverlight 5 Windows Phone 8 (Silverlight) Windows Phone 8 (Windows Runtime) Windows 8.1 We’ll also be discontinued support for .NET 4.0 for WPF. The minimum version of .NET for WPF is now 4.6.1 All of these platforms are still supported in the 3.x releases.

Changes Below is the changes included in 4.0.0 release.

Assemblies The platforms targeted have been changed to support the new .NET ecosystem. These include:

Caliburn.Micro.Core targets .NET Standard 2.0. Caliburn.Micro.Platform.Xamarin.Forms targets .NET Standard 2.0. Caliburn.Micro.Platform is consistently named across all platforms (previously UWP included the platform name) except for Xamarin.Forms. Event Aggregator The Event Aggregator has some major breaking changes, that bring it into an async implementation approach that is the main reason for 4.0.0.

The full changes are available in the event aggregator migration documentation.

Screens and view model lifecycle All the interfaces that support view model lifecycle such as IActivate and IGuardClose now support an async implementation.