void FilterNewsArticle(NewsArticle newsArticle, ExtensionFeature <INewsFilterExtension> feature = null)
        {
            if (feature == null)
            {
                feature = NewsFilterExtensionFeatures.First();
            }

            Window window = feature.Extension.CreateQuickFilterWindow(newsArticle, feature.KeyValueStorage);

            System.Diagnostics.Debug.WriteLine("window = " + window);
            if (window != null)
            {
                window.ShowDialog();
            }
            QuickFilterFinished?.Invoke(this, new EventArgs());
        }
        void ShareNewsArticle(NewsArticle article, ExtensionFeature <INewsSharerExtension> feature = null)
        {
            if (feature == null)
            {
                feature = NewsSharerExtensionFeatures.First();
            }

            NewsArticle articleToShare = new NewsArticle(article);

            articleToShare.Url = SelectMultiUrl(article.Url);
            NewsSharerWindow sharerWindow =
                feature.Extension.CreateSharerWindow(articleToShare, feature.KeyValueStorage);

            sharerWindow.JobsCreated += SharerWindow_JobsCreated;
            sharerWindow.ShowDialog();
        }