I was trying to add a reference to List<T> for use in a method.

ModuleDefinition md;
...
var listType = md.ImportDotNetType(typeof(List<>));

with

    [NotNull]
    public static TypeReference ImportDotNetType([NotNull] this ModuleDefinition md, [NotNull] Type t) {
      var ns = t.Namespace;
      var name = t.Name;
      return md.ImportReference(new TypeReference(ns, name, md, md.TypeSystem.CoreLibrary, t.IsValueType));
    }

This works perfectly fine for net472 assemblies. In a netstandard2.1 assembly, the code looks fine in ILSpy (with [netstandard]System.Collections.Generic.List`1 being shown in IL).

However, at runtime, this results in Could not load type 'System.Collections.Generic.List`1' from assembly 'System.Runtime, Version=5.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

So it looks like my import is not resolving correctly; netstandard forwards the type to System.Collections but the code is apparently expecting to find it in System.Runtime instead.

What am I missing in order for this to resolve correctly?

I have now worked around it by subclassing List<T> in my own library, so I avoid the issue (and the generics), but I'd still like to know how to make this work in the "normal" way.