marker.title is not set on leaflet.drupal.js

Problem/Motivation

Markers "alt" attribute are set to an empty string because marker.title is not set on leaflet.drupal.js.

The following code should set the title, but marker.title is "undefined" and there is no option to set this value from the frontend.

  Drupal.Leaflet.prototype.create_point = function(marker) {
    let latLng = new L.LatLng(marker.lat, marker.lon);
    let lMarker;
    let marker_title = marker.title ? marker.title.replace(/<[^>]*>/g, '').trim() : '';
    let options = {
      title: marker_title,
      className: marker.className || '',
      alt: marker_title,
    };