Select fields do not show values in Meta Box Group

Hi Clayton,

I've received your ticket via Freshdesk:

I keep getting an error when trying to submit more information on this bug. I hope all of this information goes through fine.

To recreate this issue, 
- Install Metabox and MB Groups on WP. 
- Register the group field. 
- Register the taxonomy. 
- Create taxonomy terms. 
- Create a post. 
- Select a taxonomy term with the select field in the group field. 
- Save the post. 
- Refresh the page.
What you will see is the select field has no value but the database stored the proper value from the select field. The new raw filter for the group field is preventing the field from showing the actual value. Please have a look at the first comment from this ticket to see where we think the problem is.

The field taxonomy doesn’t store any terms in the post meta. Instead, it sets post terms. Just like a replacement of Category or Tag meta box of WordPress so it does not work with Group. If you want to save the taxonomy as the post meta, please use the field taxonomy_advanced.

For more information, please follow these documentations.
https://docs.metabox.io/fields/taxonomy-advanced/
https://docs.metabox.io/fields/taxonomy/#data

Hi,
you could use a workaround. Use a simple "Select" field and fill the options with the term data from get terms. To get the terms use get_terms inside the "init" action hook.
For Example:

add_filter( 'init', function() {
    $terms = get_terms(
        [
            'taxonomy' => 'THE_TAXONOMY',
            'hide_empty' => false
        ]
    );
    $terms_data = [];
    foreach( $terms as $term ) {
        $terms_data[ $term->term_id ] = $term->name;
    }
    add_filter( 'rwmb_meta_boxes', function( $meta_boxes ) use ( $terms_data ) {
        meta_boxes[] = [
           'title'      => 'THE_METABOX',
           'post_types' => 'THE_POSTTYPE',
           'fields' => [
            [
                'name'  => 'THE_FIELD_NAME',
                'id'    => 'THE_FIELD_ID',
                'type'  => 'group',
                'fields' => [
                    [
                      'name' => 'THE_SELECT_FIELD_NAME',
                      'id' => 'THE_SELECT_FIELD_ID',
                      'type' => 'select',
                      'options' => $terms_data,
                   ],
                ]
            ],
        ];
        return $meta_boxes;
   });
}