Background

To better understand my request I describe my setup first. I host my Gentoo installation guide on Cloudflare Pages. To get things working I must have a DNS record as shown in the following code block. There is no alternative provided by Cloudflare.

❯ delv +nodnssec cname gentoo.duxsco.de
; fully validated
gentoo.duxsco.de.	294	IN	CNAME	gentoo-installation.pages.dev.

Unfortunately, this doesn't allow for any other DNS record, and that's a limitation of using CNAME records. So, a TXT record as outlined in the Keyoxide docs is not possible.

Google's Approach

Thus, I suggest a solution similiar to the one provided in the Google Search Console (formerly: Google Webmaster Tools).

As usual, they support TXT records:

screenshot

In addition, the "CNAME record" approach is supported, but you can use a subdomain which means you'll have the following DNS record that wouldn't interfere with any preexisting CNAME record.

❯ delv +nodnssec cname 5ib6t6yu6awy.example.duxsco.de
; fully validated
5ib6t6yu6awy.example.duxsco.de.	294	IN	CNAME	gv-fiyujhu5bw4inc.dv.googlehosted.com

screenshot

My request

Keyoxide should support a DNS proof where a subdomain of "gentoo.duxsco.de" is used. It can be either a predefined subdomain, e.g. "keyoxide-proof.gentoo.duxsco.de", or some hash prepended to "gentoo.duxsco.de", e.g. "ur4378rzeaf.gentoo.duxsco.de". I think the "predefined subdomain" approach is sufficient.