On Robert server – Plesk, we can add NGINX Directives to enable GZIP.
(? Google Lighthouse / Performance score is increased by 30% in average).

• Go in the setting page Paramètres d’Apache et Nginx
• At the very bottom of the page, in Directives supplémentaires Nginx, paste:

  gzip on;
  gzip_disable "MSIE [1-6]\\.(?!.*SV1)";
  gzip_proxied any;
  gzip_comp_level 5;
  gzip_types text/plain text/css application/javascript application/x-javascript text/xml application/xml application/xml+rss text/javascript image/x-icon image/bmp image/svg+xml;
  gzip_vary on;