private void ButtonBookmark_Click(object sender, EventArgs e)
 {
     // Add/Remove file from users Bookmarks
     if (Bookmarks.IsBookmarked(CurrentFile.URL))
     {
         Bookmarks.RemoveFile(CurrentFile.URL);
         ControlExtensions.SetControlText(ButtonBookmark, "Add to Bookmarks");
     }
     else
     {
         Bookmarks.AddFile(CurrentFile.URL);
         ControlExtensions.SetControlText(ButtonBookmark, "Remove from Bookmarks");
     }
 }