theming – Author image in comments twig

I succesfully get user name, surname and date to render in comment.html.twig like this

function MYTHEMENAME_preprocess_comment(&$variables) {
    $comment = $variables('comment');
    $variables('user_name_comment') = $comment->getOwner()->field_first_name->value;
    $variables('user_surname_comment') = $comment->getOwner()->field_last_name->value;
    $variables('created') = Drupal::service('date.formatter')->format($variables('comment')->getCreatedTime(), 'conference_date');
}

In node template i got field_picture to render like this

$variables('author_picture') = $node->getOwner()->field_picture->entity->url();

But i can’t get my field_picture from user to render in comment twig file. I try to show the author’s picture of every comment.

Any ideas?