{HTTP HOST} in. htaccess

Hello. There is an address https://super.loc

Why is this expression incorrect:

RewriteCond %{HTTP_REFERER} !https://{HTTP_HOST}

And does not match the expression:

RewriteCond %{HTTP_REFERER} !https://super.loc

{HTTP_HOST} after all, it returns the hostname, in this case super.loc

Author: caboke, 2020-12-16