actually it wasn't mine. But it affected me. So we had a project website on wordpress and wanted to rewrite the theme. everything went well to the Point of production. Site is fine locally, at testing and on stage. On production we still see old, a bit broken old version, but only on homepage. Wtf. Nothing helped. After couple of hours later we found out, that the admin was updating php version and he left html shot at production, which was taking over.