For documents like PDFs, there’s no way to position canonical tags inside the site header simply because there is not any site segment. In these types of conditions, you’ll must use HTTP headers to established canonicals. Use Google’s URL inspection tool if necessary to Verify particular person pages and reveal https://addons.prestashop.com/fr/seo-referencement-naturel/31857-seo-automatique-google-rich-snippets-json-ld-open-graph.html