diff --git a/src/Moq/Extensions.cs b/src/Moq/Extensions.cs
index 0cdfd2ef6..9e1522d9f 100644
--- a/src/Moq/Extensions.cs
+++ b/src/Moq/Extensions.cs
@@ -519,9 +519,9 @@ public static Type SubstituteTypeMatchers(this Type type, Type other)
             return type;
         }
 
-        private static readonly ConcurrentDictionary<Tuple<Type, Type>, InterfaceMapping> mappingsCache = new();
+        static readonly ConcurrentDictionary<Tuple<Type, Type>, InterfaceMapping> mappingsCache = new();
 
-        private static InterfaceMapping GetInterfaceMap(Type type, Type interfaceType)
+        static InterfaceMapping GetInterfaceMap(Type type, Type interfaceType)
         {
             return mappingsCache.GetOrAdd(Tuple.Create(type, interfaceType), tuple => tuple.Item1.GetInterfaceMap(tuple.Item2));
         }