<?php
add_filter( ‘rwmb_meta_boxes’, ‘your_prefix_register_meta_boxes’ );
function your_prefix_register_meta_boxes( $meta_boxes ) {
$prefix = ‘prefix-‘;
$meta_boxes[] = [
'title' => esc_html__( 'Untitled', 'online-generator' ),
'id' => 'untitled',
'post_types' => ['post'],
'context' => 'normal',
'priority' => 'high',
];
return $meta_boxes;
}