C# Compiler Error – CS8904 invalid variance: the type parameter ‘{1

In this blog post, you’ll learn more about the C# Compiler Error – CS8904 and the related message description

C# Compiler Error Code

CS8904

C# Compiler Description for the Code :CS8904

Invalid variance: The type parameter ‘{1}’ must be {3} valid on ‘{0}’ unless language version ‘{4}’ or greater is used. ‘{1}’ is {2}.