Cosmos: Getting System.ArgumentNullException when loading not primitive collection properties from stored document

[Dragon160]

Description

If I want to store and load the following structure with EntityFrameworkCore.Cosmos I receive an ArgumentNull-Exception saying:

System.ArgumentNullException: Value cannot be null. (Parameter 'arguments[3]')

It seems that the document has been written to the Cosmos DB in the correct form. But it is not possible to read it out again from the DB.

You can find a running sample project showing this issue in my repository:
https://github.com/Dragon160/EntityFrameworkCoreIssue

Code

public class BmwCar
{
    public string Owner { get; set; }
    public int Age { get; set; }
    public string Id { get; set; }

    // Does not work with List
    public IReadOnlyList<EngineInfo> EngineInfos { get; set; }

    // Works with simple property
    //public EngineInfo EngineInfo { get; set; }

    public BmwCar()
    {
        Id = Guid.NewGuid().ToString();
    }
}

public class BmwEngineInfo : EngineInfo
{
    public bool HasXDriveOption { get; set; }

    public Producer Producer { get; set; }
}

public class Producer
{
    public string Name { get; set; }
}

Expected behavior

EFC.Cosmos should be able to read the written document again.

Actual behavior

System.ArgumentNullException: Value cannot be null. (Parameter 'arguments[3]')
when executing

dbContext.BmwCars.Find("id").

Further technical details

EF Core version: 3.1.0 / 3.0.0
Database provider: Cosmos DB
Target framework: Core 3.1 / netStandard2.1
Operating system: Windows 10

[AndriySvyryd]

@Dragon160 Don't call modelBuilder.Entity<BmwEngineInfo>() https://github.com/Dragon160/EntityFrameworkCoreIssue/blob/master/EFCoreCosmosIssue.UnitTests/BmwCosmosDbContext.cs#L23

See #15681 (comment) for how to use configuration classes for owned entity types

Also owned entity types don't support inheritance yet.