> AFAIK, cloudflare only flattens CNAMEs at the root level Cloudflare nameservers also flatten CNAMEs pointing to workers.dev (a domain they own), for example.

> AFAIK, cloudflare only flattens CNAMEs at the root level Cloudflare nameservers also flatten CNAMEs pointing to workers.dev (a domain they own), for example. My intention was to point out that nameservers that flatten CNAMEs render DNS-based blocking ineffective.