Newtonsoft JSON serialize list in list

I am using a ef core database in my UWP app and have some issues serializing a list containing a list with Newtonsoft JSON.

For a minimal example consider the UWP tutorial from microsoft with the following code

public class Blog
{
    public int BlogId { get; set; }
    public string Url { get; set; }

    public List<Post> Post { get; set; }
}

public class Post
{
    public int PostId { get; set; }
    public string Title { get; set; }
    public string Content { get; set; }

    public int BlogId { get; set; }
    public Blog Blog { get; set; }
}

public class BloggingContext : DbContext
{
    public DbSet<Blog> Blogs { get; set; }
    public DbSet<Post> Posts { get; set; }

    protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        optionsBuilder.UseSqlite("Filename=minexample.db");
    }
}

when I now want to serialize some data the following way:

using (var db = new BloggingContext())
{
    var dbPost = db.Blogs.Include(x => x.Post).ToList();
    var serialized = JSONClass.Serialize(dbPost);
}

I get an error of type System.StackOverflowException in mscorlib.ni.dll that I enter an infinity loop. As user alanh mentioned in the comments, this behavior can be fixed with setting ReferenceLoopHandling to ReferenceLoopHandling.Ignore in JsonSerializerSettings.

I would prefer to just store the ID of each Post as List<int> instead of List<Post> when serializing the Blog.

Why serializing, if a database is given? I want to share specific database entries and need to serialize them. Also I consider doing this for synchronization with OneDrive, so there is no clash, when editing different database entries on different devices at different times (single user).