private static void DocumentStyle_Changed(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            MarkdownEditor source = sender as MarkdownEditor;

            if (source == null)
            {
                return;
            }

            source.markdown.DocumentStyle = (Style)e.NewValue;
        }
        private static void AssetPathRoot_Changed(DependencyObject sender, DependencyPropertyChangedEventArgs e)
        {
            MarkdownEditor source = sender as MarkdownEditor;

            if (source == null)
            {
                return;
            }

            source.markdown.AssetPathRoot = (string)e.NewValue;
        }