The target framework 'net5.0' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

The target framework 'netcoreapp3.1' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

The target framework 'netcoreapp3.0' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

Argument of type 'IEnumerable<T?>' cannot be used for parameter 'first' of type 'IEnumerable<T>' in 'IEnumerable<T> Enumerable.Concat<T>(IEnumerable<T> first, IEnumerable<T> second)' due to differences in the nullability of reference types.

Argument of type 'IEnumerable<T?>' cannot be used for parameter 'first' of type 'IEnumerable<T>' in 'IEnumerable<T> Enumerable.Concat<T>(IEnumerable<T> first, IEnumerable<T> second)' due to differences in the nullability of reference types.

Argument of type 'IEnumerable<T?>' cannot be used for parameter 'first' of type 'IEnumerable<T>' in 'IEnumerable<T> Enumerable.Concat<T>(IEnumerable<T> first, IEnumerable<T> second)' due to differences in the nullability of reference types.

The target framework 'netcoreapp3.1' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

The target framework 'net5.0' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

The target framework 'netcoreapp3.0' is out of support and will not receive security updates in the future. Please refer to https://aka.ms/dotnet-core-support for more information about the support policy.

Argument of type 'IEnumerable<T?>' cannot be used for parameter 'first' of type 'IEnumerable<T>' in 'IEnumerable<T> Enumerable.Concat<T>(IEnumerable<T> first, IEnumerable<T> second)' due to differences in the nullability of reference types.

Argument of type 'IEnumerable<T?>' cannot be used for parameter 'first' of type 'IEnumerable<T>' in 'IEnumerable<T> Enumerable.Concat<T>(IEnumerable<T> first, IEnumerable<T> second)' due to differences in the nullability of reference types.

Argument of type 'IEnumerable<T?>' cannot be used for parameter 'first' of type 'IEnumerable<T>' in 'IEnumerable<T> Enumerable.Concat<T>(IEnumerable<T> first, IEnumerable<T> second)' due to differences in the nullability of reference types.