Undefined index error

The supplied patch produces the error:

Warning: Undefined array key "" in _intlinks_build_url_options() (line 122 of /sites/all/modules/contrib/intlinks/intlinks_title_filter.inc).

Google Gemini proposed fix:

function _intlinks_build_url_options($parts, $language_list, $langcode) {
  $options = ['absolute' => FALSE];

  if ($langcode !== LANGUAGE_NONE && isset($language_list[$langcode])) {
    $options['language'] = $language_list[$langcode];
  }

  if (isset($parts['query'])) {
    $options['query'] = $parts['query'];
  }

  if (isset($parts['fragment'])) {
    $options['fragment'] = $parts['fragment'];
  }

  return $options;
}