code: function onHover (selection) {
          var feature = selection.feature;
          if (feature) {
              if (selection.changed) {
                  var info;
                  if (scene.introspection) {
                      info = getFeaturePropsHTML(feature);
                  }
                  else {
                      var name = feature.properties.name || feature.properties.kind ||
                          (Object.keys(feature.properties).length+' properties');
                      name = '<b>'+name+'</b>';
                      name += '<br>(click for details)';
                      name = '<span class="labelInner">' + name + '</span>';
                      info = name;
                  }
  
                  if (info) {
                      tooltip.setContent(info);
                  }
              }
              layer.openTooltip(selection.leaflet_event.latlng);
          }
          else {
              layer.closeTooltip();
          }
      }
docs: close tooltip when zooming