How to add referral button to the posts table

If you want to add button which link to any external information about a post: in file functions.php add next code:

add_action('tableon_profile_extend', function($profile, $action_name) {

    if ($action_name === 'tableon_default_tables') {
       
        $profile['ref_btn'] = [
            'title' => esc_html('Ref. button'),
            'order' => FALSE,
            'action' => function($post_id) {
                return TABLEON_HELPER::draw_html_item('a', [
                            'href' => get_post_meta($post_id, '_product_url', true),
                            'target' => '_blank',
                            'class' => 'tableon-btn'
                                ], 'BUTTON NAME HERE');
            }
        ];
    }

    return $profile;
}, 10, 2);