DNSOnly self-signed SSL cert

I need to renew a self-signed SSL cert on a DNSOnly server. I believe there used to be an area in the UI where I could generate a new certificate, but I can't seem to locate it this time. Was that feature removed, or am I looking in the wrong place? Under "Manage Service SSL Certificates" I can paste certificate into three textareas, but there is no option to generate a new self-signed certificate.