set current userid as default value in hidden field

Hello Leo,

Yes, it is possible. You need to use the code to get the current user ID then register the meta box and custom field and assign the user ID to the default value of the field. For example:

add_filter( 'rwmb_meta_boxes', 'your_prefix_hidden' );

function your_prefix_hidden( $meta_boxes ) {
    $current_user_id = get_current_user_id();
    
    $meta_boxes[] = [
        'title'      => __( 'hidden', 'your-text-domain' ),
        'id'         => 'hidden',
        'post_types' => ['post'],
        'fields'     => [
            [
                'id'      => 'test_hidden_field',
                'type'    => 'hidden',
                'std'     => $current_user_id,
            ]
        ],
    ];

    return $meta_boxes;
}