code: function geojsonSizeFieldV0ToV1(config) {
    const defaultRaiuds = 10;
    const defaultRadiusRange = [0, 50];
  
    // if extruded, sizeField is most likely used for height
    if (config.visConfig.extruded) {
      return 'heightField';
    }
  
    // if show stroke enabled, sizeField is most likely used for stroke
    if (config.visConfig.stroked) {
      return 'sizeField';
    }
  
    // if radius changed, or radius Range Changed, sizeField is most likely used for radius
    // this is the most unreliable guess, that's why we put it in the end
    if (
      config.visConfig.radius !== defaultRaiuds ||
      config.visConfig.radiusRange.some((d, i) => d !== defaultRadiusRange[i])
    ) {
      return 'radiusField';
    }
  
    return 'sizeField';
  }
docs: in v1 geojson stroke base on -> sizeField height based on -> heightField radius based on -> radiusField here we make our wiredst guess on which channel sizeField belongs to