This is the code snippet I found:
/* Move Featured Image Below Title */
function move_featured_image_box() {
remove_meta_box( ‘postimagediv’, ‘post_type’, ‘side’ );
add_meta_box(
‘postimagediv’, __(‘Featured Image’),
‘post_thumbnail_meta_box’, ‘post_type’, ‘normal’, ‘high’);
}
add_action(‘do_meta_boxes’, ‘move_featured_image_box’);
The problem here is the ‘post_type’ … as far as I understand this it has to be specified. But I would love to apply it to ALL post types.