Issue #3258780 by davidhk, itamair: Ajax popups: add caching & improve display

        if (content.length) {

          let url = content.data('leaflet-ajax-popup');

          Drupal.ajax({url: url}).execute().done(function () {

            // Copy the html we received via AJAX to the popup, so we won't

            // have to make another AJAX call (#see 3258780).

            e.popup.setContent(element.innerHTML);

            //Call update() so Leaflet refreshes the map, panning it if

            // necessary to bring the full popup into view (#see 3258780).

            e.popup.update();

            // Attach drupal behaviors on new content.

            Drupal.attachBehaviors(element, drupalSettings);

          });