How can I override the container.html.twig template for one submit button only?
Based somewhat on kiemi's answer, you could go for something to this degree:

&lt;?php

/**
 * Implements hook_theme_suggestions_container_alter().
 */
function yourtheme_theme_suggestions_container_alter(array &amp;$suggestions, array $variables) {
  $pieces = [
    $variables['element']['#type'],
    $variables['element']['#name'],
    $variables['element']['#display_id'],
  ];
  $suggestions[] = 'container__' . implode('_', $pieces);
}


This will produce a suggestion, for example, of container--view-articles-featured.html.twig

Of course, if you want it to follow true Drupal template suggestion standards, you'll want to add several suggestions with varying levels of specificity.