Drupal - Order array by another array

reorder-form-actions.php

<?php

// Reorder actions.
$order = [
  'previous',
  'reset',
  'submit',
  'preview_next',
];

$actions = $form['actions'];
  
uksort($actions, function ($key1, $key2) use ($order) {
  return (array_search($key1, $order) > array_search($key2, $order));
});

$i = 0;
foreach (Element::children($actions) as $key) {
  $actions[$key]['#weight'] = $i++;
}

$form['actions'] = $actions;