runtime: Introduction of JsonTypeInfo in one of the Serialize overloads breaks the code in .net 6

I have EF Core conversion lambdas as follows:

entity.Property(e => e.Value).HasConversion(v => JsonSerializer.Serialize(v,null), v => JsonSerializer.Deserialize(v, null)); where ‘v’ is a HashSet<string> . It worked in .net5

After moving to .net 6, I got this compilation error:

“The call is ambiguous between the following methods or properties: ‘JsonSerializer.Serialize<TValue>(TValue, JsonSerializerOptions?)’ and ‘JsonSerializer.Serialize<TValue>(TValue, JsonTypeInfo<TValue>)’”

This is because a new overloaded Serialize was introduced as a performance update to JsonSerializer (via https://devblogs.microsoft.com/dotnet/try-the-new-system-text-json-source-generator/ )?

However, I cannot keep null as a named parameter or omit the null as an optional parameter because it is not allowed in lambads ( CS0854, there is no documentation page for this error though: https://docs.microsoft.com/en-us/dotnet/csharp/misc/sorry-we-don-t-have-specifics-on-this-csharp-error?f1url=%3FappId%3Droslyn%26k%3Dk(CS0854))

Consequently the code needs to be changed to:

entity.Property(e => e.Value).IsRequired().HasConversion(v => JsonSerializer.Serialize(v, new JsonSerializerOptions()), v => JsonSerializer.Deserialize<HashSet<string>>(v, new JsonSerializerOptions()));