Thank you on your query. I never suggest modifying any with the core documents, when using a CMS (which include PrestaShop). This is due to it could cause challenges if you up grade the software program later. From the configuration of the Google Integrator module you are able to configure https://automatische-google-rich06050.nico-wiki.com/1198326/5_tips_about_prestashop_canonical_url_you_can_use_today