In 2010, Microsoft released Samples for Parallel Programming with the .NET Framework (archive), along with the ParallelExtensionsExtras, a library of various extensions, which was based on .NET Framework 4. This is a port of sample ParallelExtensionsExtras source code, targeting .NET Framework 4.0, .NET Framework 4.5, .NET Standard 2.0, and .NET 6.0.
For examples of how to use this library, please refer to the series of blog posts by Stephen Toub.
The following APIs are available only when targeting .NET Framework 4+ and .NET 6+ Windows Desktop:
System.Threading.Tasks.AsyncCall.CreateInTargetAppDomain<T>System.Threading.Tasks.TaskExtrasExtensions.WaitWithPumping