code: def eventFilter( self, object, event ):
          
          if ( event.type() == event.Resize and \
               self.currentMode() == XOrbBrowserWidget.Mode.Thumbnail and \
               self.isGroupingActive() ):
              size = QSize(event.size().width() - 20, 22)
              for row in range(object.count()):
                  item = object.item(row)
                  if ( isinstance(item, GroupListWidgetItem) ):
                      item.setSizeHint(size)
          return False
docs: Processes resize events on the thumbnail widget to update the group
          items to force a proper sizing.
          
          :param      object | <QObject>
                      event  | <QEvent>
          
          :return     <bool> | consumed