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Not solved because in the sidebar I get the list of the specific post and not the complete list of registered taxanomy terms!

Hello I tried to get something like to be have a list of all the taxonomy list in a sidebar widget but I get only a blank space of the item in hmtl content space.

<?php
$terms = get_terms( array(
'taxonomy' => 'categorie', 
'orderby' => 'name', 
'order' => 'ASC',
'hide_empty' => true, 
));
if ( empty( $terms ) || is_wp_error( $terms ) ) {
return;
}
foreach( $terms as $term ) {
    $cat_title= rwmb_meta( 'categorie', ['object_type' => 'term'], $term->name );
	echo '<ul><li>';
    echo'<a href="'. get_term_link( $term ) .'">'. $cat_title . '</a>';
    echo '</li></ul>';
}
?>

https://www.maxxdesign.it/gremesefr/livre/ghost/

Can you explain me where is the bug in my code?

Hello
I had a simlar problem that I tried to solve switching to a clonable group of fields (this is a book catalogue and in some cases I need to add the authors names with pictures, but only to make them visible in the authors' list page).
Following and aexample showed on Mteboax Group page I create this group in $meta_boxes:

[
                'name' => esc_html__( 'Autori vari', 'online-generator' ),
                'id'         => 'extra',
                'type'       => 'group', 
                'clone'      => true,
                'clone_as_multiple' => true,     
                'sort_clone' => true, 
                'add_button' => '+ Aggiungi nuovo',    

                // List of sub-fields.
                'fields'     => [
                    [
                'type' => 'text',
                'name' => esc_html__( 'Nome', 'online-generator' ),
                'id'   => 'author_name',
                    ],
                    [
                'type' => 'text',
                'name' => esc_html__( 'Cognome', 'online-generator' ),
                'id'   => 'author_surname',
                    ],
                    [
                'type'             => 'image',
                'name'             => esc_html__( 'Foto', 'online-generator' ),
                'id'               => 'author_pict',
                'max_file_uploads' => 1,
                    ],

Then following the query example I added this code in the page template:

<?php
		
   $authors = rwmb_meta( 'extra' );
   if ( ! empty( $authors ) ) {
    foreach ( $authors as $author ) {
        echo '<h4>', 'Auteurs d\'Ouvrages Collectif', '</h4>';
        echo '<p>', 'Prénom:', ' ', $author['author_name'], '</p>';
        echo '<p>', 'Nom:', ' ', $author['author_surname'], '</p>';
            }
}
?>

But the query issue is only blank!
Instead the query to normal fields (not in clonable group) let me show the books' authors in perfect descending surname order.
See the page here

I built a field group to manage books in a catalogue where there are multiple authors for a single book (on frontend will not be shown the authors surnames but only the text 'Ouvrage collectif')
The problem comes when I try to retreive all the authors in alphabetical order (eventually is there a picture too, but the question is secondary!).
The query to clonable fields gives me a blank space...
I tried to set a * in array or a blank space or all the capital letters from A to Z.
My deal is to retreive all the author's surname then match them with names and with uploaded picture file.
The same code - using a single text input - for books with only one author - works fine:

Here the code used for field group and query

$prefix = 'edgr_';

    $meta_boxes[] = [
        'title'    => esc_html__( 'Inserimento Autori vari', 'online-generator' ),
        'id'         => 'bookauthors',
        'post_types' => ['livre'],
        'context'  => 'after_title',
        'autosave' => true,
        'fields'   => [
            [
                'type'  => 'text',
                'name'  => esc_html__( 'Cognome', 'online-generator' ),
                'id'    => $prefix . 'cloned_surname',
                'desc'  => esc_html__( 'inserire cognome', 'online-generator' ),
                'clone' => true,
            ],
            [
                'type'  => 'text',
                'name'  => esc_html__( 'Nome', 'online-generator' ),
                'id'    => $prefix . 'cloned_name',
                'desc'  => esc_html__( 'inserire nome', 'online-generator' ),
                'clone' => true,
            ],
            [
                'type'  => 'image',
                'name'  => esc_html__( 'Image', 'online-generator' ),
                'id'    => $prefix . 'cloned_author_img',
                'clone' => true,
            ],
        ],
    ];

-----

 $new_args = array(
     'post_type' => 'livre',
     'meta_query' => array(
      array(
      'key' => 'edgr_cloned_surname',
      'value'   =>  serialize( array( ????? ) ),
      'compare' => 'LIKE',
     )
     ),
     'posts_per_page' => '-1',
     'order' => 'ASC',
     'orderby' => array(
     'edgr_cloned_surname' => 'ASC',
     )
     );
    ?>
<?php $new_query = new WP_Query( $new_args ); ?>
<?php if ($new_query->have_posts()) : while ($new_query->have_posts()) : $new_query->the_post(); ?> 
    <div class="card">   
   <?php
    $author_c_surname = get_post_meta($post->ID, 'edgr_cloned_name', true);
    $author_c_name = get_post_meta($post->ID, 'edgr_cloned_surname', true);
    ?>
    <?php echo '<h5 class="book-author"><a href="' .$link. '">'.$author_c_name.'&nbsp;'.  $author_c_surname.'</a></h5>'; ?>
    </div>
     <?php 
	 endwhile; 
	 endif;

Hello
is there a way to set a limit (maximum) of choices in a multiselect dropdown field?