Yes – i have the same problem
Code in meta-boxes.php looks like:
/**
* Display post thumbnail meta box.
*
* @since 2.9.0
*/
function post_thumbnail_meta_box() {
global $post;
$thumbnail_id = get_post_meta( $post->ID, ‘_thumbnail_id’, true );
echo _wp_post_thumbnail_html( $thumbnail_id );
}
Code in edit_form_advanced.php looks like:
if ( current_theme_supports( ‘post-thumbnails’, $post_type ) && post_type_supports( $post_type, ‘thumbnail’ )
&& ( ! is_multisite() || ( ( $mu_media_buttons = get_site_option( ‘mu_media_buttons’, array() ) ) && ! empty( $mu_media_buttons[‘image’] ) ) ) )
add_meta_box(‘postimagediv’, __(‘Featured Image’), ‘post_thumbnail_meta_box’, $post_type, ‘side’, ‘low’);
… nothing effect to change Parameter