The module automatically adds a default canonical url to all of your item, group, CMS pages only. By default, the module employs the current url of your site as the default canonical url. The sitemap also helps you to modify any characteristics, such as hreflang. It provides an easily readable https://addons.prestashop.com/en/seo-natural-search-engine-optimization/31857-automatic-google-rich-snippets-json-ld-open-graph-seo.html