The variable 'ex' is declared but never used

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

The variable 'ex' is declared but never used

Cannot convert null literal to non-nullable reference type.

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

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.

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

Cannot convert null literal to non-nullable reference type.

Nullability of reference types in type of parameter 'state' of 'void UdpTimedSender.SendMessageCallback(object state)' doesn't match the target delegate 'TimerCallback' (possibly because of nullability attributes).