themes-wordpress/chanson/patterns/404.php

<?php
/**
 * Title: A 404 page
 * Slug: chanson/404
 * Inserter: no
 */
declare( strict_types = 1 );
?>

<!-- wp:paragraph -->
<p><?php echo  esc_html__( '⌇⌇ Oops, this page cannot be found.', 'chanson' ); ?></p>
<!-- /wp:paragraph -->