Possible null reference argument for parameter 'callback' in 'EventCallback<MouseEventArgs> EventCallbackFactory.Create<MouseEventArgs>(object receiver, Action callback)'.

Dereference of a possibly null reference.

Dereference of a possibly null reference.

Cannot convert null literal to non-nullable reference type.

Non-nullable property 'MudComboBox' must contain a non-null value when exiting constructor. Consider adding the 'required' modifier or declaring the property as nullable.

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)'.

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.