void IViewModel.OnChangeHistoryItemDoubleClicked(IStateHistoryItem item)
 {
     if (item is StateHistoryItem historyItem)
     {
         ShowPropertyChange(historyItem.Event, retainFocus: false);
     }
 }
 void IViewModel.OnChangeHistoryItemKeyEvent(IStateHistoryItem item, Key key)
 {
     if (item is StateHistoryItem historyItem)
     {
         if (key == Key.Enter)
         {
             ShowPropertyChange(historyItem.Event, retainFocus: true);
         }
         else if (key == Key.BookmarkShortcut)
         {
             ToggleBookmark(historyItem.Event);
         }
     }
 }