Add a simple "Cancel" button / link to a modern Drupal form

Adding a simple "Cancel" button to a form, which points to a route is easy, but you have to know how:

$form['actions']['cancel'] = [
  '#type' => 'link',
  '#title' => t('Cancel'),
  '#attributes' => [
    'class' => [
      'button',
      'button--danger',
      'button--cancel',
    ],
  ],
  '#url' => Url::fromRoute('your.route'), // Set your route here
  '#weight' => -1,
];