anchor.diff:      _activeTimer = Timer(
           Duration(
               milliseconds:
  -                currentTime - _lastRequestTime + delayBetweenRequests), () {
  +                currentTime - _lastRequestTime! + delayBetweenRequests), () {
         _activeTimer = null;
         requestScheduledButNotStarted = false;
         _performRequest();
  
positive.code:       _pendingRequest = Completer();
        await callback();
      } finally {
        _pendingRequest.complete(null);
      }
    }
  
  
negative.code:     _maxTimer?.cancel();
      _maxTimer = null;
  
      _closure!();
      _closure = null;
    }
  }
  