[System.Text.Json] ReferenceHandler: how to use custom reference identifiers instead of $ref, $id and $values

[raffaeler]

I already have an existing serialization format that I can't change.
The references to the parent objects are already expressed as string Ids that are meaningful in the application.

The goal is to navigate the entire graph forward and backward using the CLR references that are identified by the already existing identifiers instead of $ref, $id and $values

How can I use the existing identifiers properties to deserialize and serialize the graph?

Thanks