Markup can be simply checked through schema markup testing Instrument. It takes some time for rich snippets to look in search results, so that they will not be displayed instantly. Having said that, product and class rich snippets will show up only immediately after Google indexes the material. I'll update https://addons.prestashop.com/de/seo-suchmaschinenranking-optimization/31857-automatische-google-rich-snippets-json-ld-opengraph-seo.html