You specify the main URL since the internet search engine could have problem identifying which 1 need to be the key URL.  The next tutorial will explain to you the way to permit Canonical URLs in Prestashop 1.five. You will find three ways so as to add hreflang tags https://addons.prestashop.com/nl/seo-zoekmachineoptimalisatie-vermelding/31857-automatische-google-rich-snippets-json-ld-opengraph-seo.html