Play video on click does not work in Chrome

Adding this preprocess seems to do the trick:

/**
 * Implements hook_preprocess_video_embed_iframe().
 */
function vefta_preprocess_video_embed_iframe(&$variables) {
  // Add an allow attribute to all Youtube iframes.
  if (strpos($variables['theme_hook_original'], 'youtube') !== FALSE) {
    $variables['attributes']->setAttribute('allow', 'autoplay; fullscreen');
  }
}

See https://developers.google.com/web/updates/2017/09/autoplay-policy-change...

And here is a patch file.