Non-nullable property 'Data' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Message' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable field 'username' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable field 'password' must contain a non-null value when exiting constructor. Consider declaring the field as nullable.

Non-nullable property 'CoraPackageInfo' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'WidgetContextType' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'WidgetCustomSettingsType' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'WidgetCustomSettingsContextType' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Name' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable property 'Description' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.

Non-nullable event 'CollectionPropertyChanged' must contain a non-null value when exiting constructor. Consider declaring the event as nullable.

Non-nullable event 'CollectionPropertyChanged' must contain a non-null value when exiting constructor. Consider declaring the event as nullable.

Nullability of reference types in type of parameter 'sender' of 'void ItemsObservableCollection<T>.OnItemsPropertyChanged(object sender, PropertyChangedEventArgs e)' doesn't match the target delegate 'PropertyChangedEventHandler' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'sender' of 'void ItemsObservableCollection<T>.OnCollectionChangedChanged(object sender, NotifyCollectionChangedEventArgs e)' doesn't match the target delegate 'NotifyCollectionChangedEventHandler' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'sender' of 'void ItemsObservableCollection<T>.OnItemsPropertyChanged(object sender, PropertyChangedEventArgs e)' doesn't match the target delegate 'PropertyChangedEventHandler' (possibly because of nullability attributes).

Nullability of reference types in type of parameter 'sender' of 'void ItemsObservableCollection<T>.OnItemsPropertyChanged(object sender, PropertyChangedEventArgs e)' doesn't match the target delegate 'PropertyChangedEventHandler' (possibly because of nullability attributes).

Possible null reference return.

Converting null literal or possible null value to non-nullable type.

Dereference of a possibly null reference.