Reusing field groups

Hello Yasmine,

You can define an array of custom fields that is not changed across field groups (reusable), then use the function array_merge() to add more fields to the reusable field group to other field groups for your requirements. For example:

add_filter( 'rwmb_meta_boxes', 'your_prefix_function_name' );
function your_prefix_function_name( $meta_boxes ) {
    // Reusing field group 1
    $field_group_1 = [
        [
            'name'          => __( 'Datetime', 'your-text-domain' ),
            'id'            => 'datetime_jeq28wycry',
            'type'          => 'datetime',
        ]

    ];

    $additional_fields = [
        [
            'name' => __( 'Custom Html', 'your-text-domain' ),
            'type' => 'custom_html',
        ],

    ];

    $field_group_2 = array_merge( $field_group_1, $additional_fields );

    $meta_boxes[] = [
        'title'  => __( 'Field Group 1', 'your-text-domain' ),
        'id' => 'field-group-1',
        'post_types' => 'page',
        'fields' => $field_group_1,
    ];

    $meta_boxes[] = [
        'title'  => __( 'Field Group 2', 'your-text-domain' ),
        'id' => 'field-group-2',
        'post_types' => 'page',
        'fields' => $field_group_2,
    ];

    return $meta_boxes;
}