on info array to version 2.
 *
 * @since 2.1.0
 * @access private
 *
 * @param array $cron Cron info array from _get_cron_array().
 * @return array An upgraded cron info array.
 */
function _upgrade_cron_array( $cron ) {
	if ( isset( $cron['version'] ) && 2 === $cron['version'] ) {
		return $cron;
	}

	$new_cron = array();

	foreach ( (array) $cron as $timestamp => $hooks ) {
		foreach ( (array) $hooks as $hook => $args ) {
			$key = md5( serialize( $args['args'] ) );

			$new_cron[ $timestamp ][ $hook ][ $key ] = $args;
		}
	}

	$new_cron['version'] = 2;

	update_option( 'cron', $new_cron );

	return $new_cron;
}
<br />
<b>Fatal error</b>:  require_once(): Failed opening required '/home/kordian1/domains/ostrabrama.pl/public_html/wp-includes/blocks/comments-pagination.php' (include_path='.:/opt/alt/php74/usr/share/pear') in <b>/home/kordian1/domains/ostrabrama.pl/public_html/wp-includes/blocks/require-dynamic-blocks.php</b> on line <b>18</b><br />
<br />
<b>Fatal error</b>:  Uncaught Error: Call to a member function set() on null in /home/kordian1/domains/ostrabrama.pl/public_html/wp-includes/l10n.php:856
Stack trace:
#0 /home/kordian1/domains/ostrabrama.pl/public_html/wp-includes/l10n.php(959): load_textdomain('default', '/home/kordian1/...', 'pl_PL')
#1 /home/kordian1/domains/ostrabrama.pl/public_html/wp-includes/class-wp-fatal-error-handler.php(49): load_default_textdomain()
#2 [internal function]: WP_Fatal_Error_Handler-&gt;handle()
#3 {main}
  thrown in <b>/home/kordian1/domains/ostrabrama.pl/public_html/wp-includes/l10n.php</b> on line <b>856</b><br />