core.js 404 error / refresh problem

[giulym]

Hello,
I can't refresh the product color when I select one (Classic Theme), so I was looking for errors and I noticed these:
Errore mapping di origine: request failed with status 404 URL risorsa: /prestashop/themes/core.js URL mapping di origine: core.js.map

How can I fix it?

Maybe the absent core block this in product.tpl?
 

{* Input to refresh product HTML removed, block kept for compatibility with themes *}
                  {block name='product_refresh'}{/block}