'TestPackageManagerViewModel.BrowseOpenFile(out string, out bool)': return type must be 'Task<bool>' to match overridden member 'PackageManagerViewModel<PackageManagerViewModelPackage, TestPackageContent>.BrowseOpenFile(out string, out bool)'

'TestPackageManagerViewModel.BrowseSaveFile(out string)': return type must be 'Task<bool>' to match overridden member 'PackageManagerViewModel<PackageManagerViewModelPackage, TestPackageContent>.BrowseSaveFile(out string)'

Process completed with exit code 1.

Node.js 16 actions are deprecated. Please update the following actions to use Node.js 20: actions/checkout@v2, actions/setup-dotnet@v1. For more information see: https://github.blog/changelog/2023-09-22-github-actions-transitioning-from-node-16-to-node-20/.

The following actions uses node12 which is deprecated and will be forced to run on node16: actions/checkout@v2, actions/setup-dotnet@v1. For more info: https://github.blog/changelog/2023-06-13-github-actions-all-actions-will-run-on-node16-instead-of-node12-by-default/

Nullability of reference types in type of 'event PropertyChangedEventHandler PackageContent.PropertyChanged' doesn't match implicitly implemented member 'event PropertyChangedEventHandler? INotifyPropertyChanged.PropertyChanged'.

Cannot convert null literal to non-nullable reference type.

Nullability of reference types in type of 'event PropertyChangedEventHandler ChangeListener.PropertyChanged' doesn't match implicitly implemented member 'event PropertyChangedEventHandler? INotifyPropertyChanged.PropertyChanged'.

Nullability of reference types in type of 'event NotifyCollectionChangedEventHandler ChangeListener.CollectionChanged' doesn't match implicitly implemented member 'event NotifyCollectionChangedEventHandler? INotifyCollectionChanged.CollectionChanged'.

Non-nullable event 'PropertyChanged' 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 CollectionChangeListener.Value_CollectionChanged(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 CollectionChangeListener.Listener_PropertyChanged(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 CollectionChangeListener.listener_CollectionChanged(object sender, NotifyCollectionChangedEventArgs e)' doesn't match the target delegate 'NotifyCollectionChangedEventHandler' (possibly because of nullability attributes).

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