Drupal t() function does not replace placeholders for me
It looks like electrokate installed a Pattern Lab starter theme for Drupal that has a mock of the t() function that acts as a placeholder for prototyping the front end layer. It only returns the input it was sent, so it "works" under Pattern Lab - but running it inside of Drupal will cause this issue.

/**
 * @file
 * Drupal translate filter.
 */
$filter = new Twig_SimpleFilter('t', function ($string) {
  return $string;
});


This is meant to aid in making a Pattern Lab prototype outside of Drupal, but taking advantage of functions you will expect to use inside of Drupal so it is "Drupal ready".

edit: I may have linked to the wrong starter theme, but I can’t navigate it on mobile.