basically code like:

using static System.Console;

public class C
{
public void M()
{
Console.WriteLine("Test"); // this would cause APIUpdater to crash.
}
}

You can workaround this issue by removing the unnecessary type reference in the invocation of WriteLine() so M() method becomes:

public void M()
{
WriteLine("Test");
}

For related discussion, please see forum https://forum.unity.com/threads/api-updater-not-explicit-at-all.488046/