Serialize error in System.Text.Json if ctor has "in" or "ref" keyword

SerializeErrorInSystemJson.cs

// TargetFramework: net6.0
// this can be avoided if there is ctor with no "ref" or "in".

using System.Text.Json;
int z = 0;
var c1 = new C1(ref z);
try
{
    JsonSerializer.Serialize(c1);
}
catch (Exception e)
{
    Console.WriteLine($"c1 error: {e}");
}
class C1
{
    // if public ctor with no ref and in, no exception.
    // public C1(){}
    public C1(ref int x)
    {

    }
}

zz-error.txt

c1 error: System.ArgumentException: The type 'System.Int32&' may not be used as a type argument.
   at System.RuntimeType.ThrowIfTypeNeverValidGenericArgument(RuntimeType type)
   at System.RuntimeType.SanityCheckGenericArguments(RuntimeType[] genericArguments, RuntimeType[] genericParameters)
   at System.RuntimeType.MakeGenericType(Type[] instantiation)
   at System.Text.Json.Serialization.Converters.ObjectConverterFactory.CreateConverter(Type typeToConvert, JsonSerializerOptions options)
   at System.Text.Json.Serialization.JsonConverterFactory.GetConverterInternal(Type typeToConvert, JsonSerializerOptions options)
   at System.Text.Json.JsonSerializerOptions.GetConverterInternal(Type typeToConvert)
   at System.Text.Json.JsonSerializerOptions.DetermineConverter(Type parentClassType, Type runtimePropertyType, MemberInfo memberInfo)
   at System.Text.Json.Serialization.Metadata.JsonTypeInfo.GetConverter(Type type, Type parentClassType, MemberInfo memberInfo, Type& runtimeType, JsonSerializerOptions options)
   at System.Text.Json.JsonSerializerOptions.<InitializeForReflectionSerializer>g__CreateJsonTypeInfo|112_0(Type type, JsonSerializerOptions options)
   at System.Text.Json.JsonSerializerOptions.GetClassFromContextOrCreate(Type type)
   at System.Text.Json.JsonSerializerOptions.GetOrAddClass(Type type)
   at System.Text.Json.JsonSerializer.GetTypeInfo(JsonSerializerOptions options, Type runtimeType)
   at System.Text.Json.JsonSerializer.Serialize[TValue](TValue value, JsonSerializerOptions options)
   at Program.<Main>$(String[] args) in D:\src\gitrepos\dotnet-sandbox\jsonnettest\Program.cs:line 6