Remove dependency on container.id

This Code Block

    $('#' + this.container.id).on({
      'dragover dragenter': function (e) {
        e.preventDefault();
        e.stopPropagation();
      },
      'drop': function (e) {
        let dataTransfer = e.originalEvent.dataTransfer;
        if (dataTransfer && dataTransfer.files.length) {
          e.preventDefault();
          e.stopPropagation();
          $.each(dataTransfer.files, function (i, file) {
            let reader = new FileReader();
            reader.onload = $.proxy(function (file, event) {
              if (file.name.match('.+(\.swc)$')) {
                let name = file.name.split('.')[0];
                let json = {};
                json[name] = {
                  label: name,
                  dataStr: event.target.result,
                  filetype: 'swc'
                };
                ffbomesh.addJson({ ffbo_json: json });
              }
            }, this, file);
            reader.readAsText(file);
          });
        }
      }
    });

was written to enable drag-dropping files onto the neu3d widget relies on container.id being specified because it uses JQuery.

Change this to use JavaScript's native method, see here

fruitflybrain / neu3d

Remove dependency on container.id #4