Featured Image Meta Box does not show up

Hi,

I have the same error.

I’m running WordPress 4.0 on a local server (wampserver) and have desactivated all plugins except “Custom Post Type UI”.

Here is my custom type code generated by the plugin if it can help :

add_action('init', 'cptui_register_my_cpt_voyant');
function cptui_register_my_cpt_voyant() {
register_post_type('voyant', array(
'label' => 'Voyants',
'description' => 'Profil de voyant par SMS.',
'public' => true,
'show_ui' => true,
'show_in_menu' => true,
'capability_type' => 'post',
'map_meta_cap' => true,
'hierarchical' => false,
'rewrite' => array('slug' => 'voyant', 'with_front' => true),
'query_var' => true,
'supports' => array('title','editor','custom-fields','thumbnail','page-attributes','post-formats'),
'labels' => array (
  'name' => 'Voyants',
  'singular_name' => 'Voyant',
  'menu_name' => 'Voyants',
  'add_new' => 'Add Voyant',
  'add_new_item' => 'Add New Voyant',
  'edit' => 'Edit',
  'edit_item' => 'Edit Voyant',
  'new_item' => 'New Voyant',
  'view' => 'View Voyant',
  'view_item' => 'View Voyant',
  'search_items' => 'Search Voyants',
  'not_found' => 'No Voyants Found',
  'not_found_in_trash' => 'No Voyants Found in Trash',
  'parent' => 'Parent Voyant',
)
) ); }

In my case both “post-formats” and “thumbnail” aren’t displayed.

Fixed!

It wasn’t a bug at all.

My custom theme just doesn’t support the feature… :/

@michael Beckwith: Sorry for the mistake.

@nolaandy: to unable thumbnails in post/page and any custom_post_type, simply add this code to your theme ‘function.php’ page :
add_theme_support( 'post-thumbnails' );