anchor.diff:    map.addSource('pins', {
      type: 'geojson',
      data: {
  -       "type": "FeatureCollection",
  +     "type": "FeatureCollection",
          "features": pinFeatures
       }
     });
  
positive.code: 
  
  map.on('click', function(event) {
    var el = document.createElement('div');
    var marker = new mapboxgl.Marker(el)
    .setLngLat(event.lngLat)
  
negative.code:     layout: {
        "icon-image": "star-15",
        "icon-allow-overlap": true
      }
    })
  
    map.getSource('pins').setData({
  