UserFiles select one thumbinails

UserFiles.tpl

{'!pdoResources' | snippet: [
  'parents' => $_modx->resource.id,
  'limit' => 0,
  'tvPrefix' => '',
  'tpl' => '',
  'leftJoin' => [
    'UF' => [
      'class' => 'UserFile',
      'on' => 'UF.parent = modResource.id AND UF.rank = 0'
    ]
  ],
  'select' => [
    'modResource' => '*',
    'UF' => 'url as thumb'
  ],
  'showLog' => 1,
    'where' => [
  ],
  'sortdir' => 'ASC'
]}