private void ViewModelOnPropertyChanged(object sender, PropertyChangedEventArgs e)
        {
            if (ViewModel == null)
            {
                return;
            }

            if (e.PropertyName == "Description")
            {
                if (string.IsNullOrEmpty(ViewModel.Description))
                {
                    return;
                }

                HyperlinkHighlighter.HighlightUrls(ViewModel.Description, DescriptionRcTbx);
                return;
            }

            if (e.PropertyName != "IsSubscribed")
            {
                return;
            }

            ClearAppBar();
            AddAppBarButtons();
        }
        private static void TextChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var richTextBox = d as RichTextBox;

            if (richTextBox == null)
            {
                return;
            }

            if (e.NewValue == null)
            {
                return;
            }

            HyperlinkHighlighter.HighlightUrls(e.NewValue.ToString(), richTextBox);
        }