If we take the example from the docs (link), a workaround is to initialize the collection with a list:
public IEnumerable<SampleData> SelectedItems { get; set; } = new List<SampleData>();
The issue is due to a bug in the framework where Enumerable.Empty() resolves to null: https://github.com/dotnet/runtime/issues/27552.
Regards,
Marin Bratanov
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