WooCommerce: cut shipping option ids if they exceed 50-chars length

functions.php

<?php 
// Paste everything below this line to your child-theme's functions.php file.

// Cut shipping option ids if they exceed 50-chars length.
add_filter('woocommerce_package_rates', function ($rates) {
    $shortened = array();
    foreach ($rates as $rate_id => $rate) {
        $rate_id = substr($rate_id, 0, 50);
        $rate->id = $rate_id;
        $shortened[$rate_id] = $rate;
    }
    return $shortened;
});