I created a block list for known DoH servers here:
It is based on these two other projects and combines their efforts:
- GitHub - MohamedElashri/doh-list: List of public DoH providers
- GitHub - crypt0rr/public-doh-servers: A simple list with public DNS-over-HTTPS (DOH) providers so you can easily block them.
It parses the content from these two sources and compiles a list usable with Pi-hole:
The list is updated once a week. Maybe some of you find it useful.