Control for selecting multiple columns [pgadmin4]

{
  id: 'columns', label: '{{ _('Columns') }}',
  type: 'collection', group: '{{ _('Definition') }}', editable:true,
  canDelete: true, canAdd: true, control: Backform.MultiColumnSelectControl,
  deps: ['index'], node: 'column',
  model: pgBrowser.Node.Model.extend({
    keys: ['column'],
    defaults: {
      column: undefined
    }
  })
}