At "Setting up or Fixing File Permissions" we got this:

https://symfony.com/doc/current/setup/file_permissions.html#1-using-acl-on-a-system-that-supports-setfacl-linux-bsd

HTTPDUSER=$(ps axo user,comm | grep -E '[a]pache|[h]ttpd|[_]www|[w]ww-data|[n]ginx' | grep -v root | head -1 | cut -d\ -f1)
# if this doesn't work, try adding -n option

But where to add -n option ?
grep, head and cut all have -n option.

A few more word would be very clear for the user who is reading this doc