This async method lacks 'await' operators and will run synchronously. Consider using the 'await' operator to await non-blocking API calls, or 'await Task.Run(...)' to do CPU-bound work on a background thread.

This async method lacks 'await' operators and will run synchronously. Consider using the 'await' operator to await non-blocking API calls, or 'await Task.Run(...)' to do CPU-bound work on a background thread.

Dereference of a possibly null reference.

Dereference of a possibly null reference.

Possible null reference argument for parameter 'collection' in 'HashSet<T?>.HashSet(IEnumerable<T?> collection, IEqualityComparer<T?>? comparer)'.

Nullability of reference types in value of type 'Converter<T?>' doesn't match target type 'Converter<T, string>'.

Possible null reference argument for parameter 'collection' in 'HashSet<T?>.HashSet(IEnumerable<T?> collection, IEqualityComparer<T?>? comparer)'.

Cannot convert null literal to non-nullable reference type.

The type 'T' cannot be used as type parameter 'TKey' in the generic type or method 'Dictionary<TKey, TValue>'. Nullability of type argument 'T' doesn't match 'notnull' constraint.