This is a new C# 8.0 feature: https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-8.0/default-interface-methods https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/tutorials/default-interface-methods-versions https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/tutorials/mixins-with-default-interface-methods MOSA currently assumes that interface classes contain no actual implementations.
This is a new C# 8.0 feature:
https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-8.0/default-interface-methods
https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/tutorials/default-interface-methods-versions
https://docs.microsoft.com/en-us/dotnet/csharp/whats-new/tutorials/mixins-with-default-interface-methods
MOSA currently assumes that interface classes contain no actual implementations.