feeds-8.x-3.0-alpha1/templates/feeds_feed.html.twig

{%
  set classes = [
    'feeds_feed',
    'feeds_feed--feed-type-' ~ feed.bundle|clean_class,
    feed.isActive() ? 'feeds_feed-active',
    view_mode ? 'feeds_feed--view-mode-' ~ view_mode|clean_class,
  ]
%}

<article{{ attributes.addClass(classes) }}>
  <div{{ content_attributes.addClass('feeds_feed__content') }}>
    {{ content }}
  </div>
</article>