How to rename the "Published on" text in the post edit publish metabox

For that you need to edit wordpress core file .

Are you sure? ??

Do you know which file I’d need to edit?

wp-admin/includes/meta-boxes.php line 170

I found this piece of code but it’s not working for me… can anyone help?

https://wordpress.stackexchange.com/questions/23566/change-the-published-on-text

add_filter( 'gettext', 'filter_published_on', 10000, 2 );
function filter_published_on( $trans, $text ) {

    if( 'Published on: <b>%1$s</b>' == $text ) {
        global $post;
        switch( $post->post_type ) {
            case 'your-posttype':
                return 'Whatever on: <strong>%1$s</strong>';
            break;
            default:
                return $trans;
            break;
        }
    }
    return $trans;
}

“Say What” plugin