title: how can I fix the error "Lighthouse returned error: NO_FCP." returned by "PageSpeed Insights" on my site "Wordpress" after install of a cache module
body: <p>I have just posted a Wordpress site with the Hoteller theme, I perform "PageSpeed Insights" tests but when I install a cache management plugin (WP Fast Cache, WP Super Cache, W3 Total Cache) without special configuration I find this error message.</p>
  
  <blockquote>
    <p>Lighthouse returned error: NO_FCP. Un problème est survenu lors de l'enregistrement de la trace du chargement de votre page. Veuillez relancer Lighthouse. (NO_FCP)</p>
  </blockquote>
  
  <p>I do not really know where to look, it's annoying for me not to optimize this site, someone would have a track to give me?</p>