List of objects in json configuration issue

[aodpi]

I'm creating a json file that I wish to add in configuration through configuration.AddJsonFile() with the following structure:

{
  "JsonLocalizerOptions": {
    "SupportedLanguages": [
      {
        "Identifier": "ro-MD",
        "Name": "Romana"
      }
    ]
  }
}

then I have a POCO class for it:

public class JsonLocalizerOptions
{
    #region Private backing fields (Default Values)
    private List<Language> supportedLanguages = new List<Language>()
    {
        new Language
        {
            Identifier = "en",
            Name = "English"
        },

        new Language
        {
            Identifier = "ro",
            Name = "Română"
        },

        new Language
        {
            Identifier ="ru",
            Name ="Русский"
        }
    };
    #endregion

    public JsonLocalizerOptions() { }

    #region Public Properties
    public List<Language> SupportedLanguages
    {
        get => supportedLanguages;
        set => supportedLanguages = value;
    }
    #endregion
}

The problem is that when I call services.Configure<JsonLocalizerOptions>(Configuration.GetSection(nameof(JsonLocalizerOptions))) the value object from the setter of the property SupportedLanguages contains the default list of the languages plus that one object from the json file. I think this is bizarre, I thought that when I call Configure I should receive the data from the json file, not my current data appending that one from json or the same data from the private field even though the setter is accessed.

Is this really how it should work?

[shirhatti]

Dupe of #694