Let's Encrypt SSL with wildcard certificates

In HestiaCP github I can read: “Let’s Encrypt SSL with wildcard certificates”. Is this working yet? How can I use it?

You need to run your dns services on your hestia server, then add a *.domain.tld and enable let’s encrypt - this will generate you a wildcard certificate. It needs a dns record for authentification, this can only work when you use a master-slave dns server combo using hestia only.

I have pointed my registrar nameservers to HestiaCP Bind9 server and a backup dns server (in FreeDNS) using the child-ns template, but I cannot find out the contents of the dns registry for LE.

On the other hand, I would like to obtain the certificate for my entire domain “domain.tld”, not just for “* .domain.tld” and its subdomains.