pi-hole:development ← pi-hole:new/disable-firefox-doh
opened 06:48AM - 07 Sep 19 UTC
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**What does this PR aim to accomplish?:**
Prevent Firefox from using DNS-over-HTTPS (DoH) as this would corrupt our efforts to block ads.
**How does this PR accomplish the above?:**
We follow the [official Mozilla Support platform](https://support.mozilla.org/en-US/kb/configuring-networks-disable-dns-over-https):
> Network administrators may configure their networks as follows to signal that their local DNS resolver implemented special features that make the network unsuitable for DoH:
>
> DNS queries for the A and AAAA records for the domain “[use-application-dns.net](http://use-application-dns.net)” must respond with NXDOMAIN rather than the IP address retrieved from the authoritative nameserver.
We we implement such a "special feature", we implement this.
**What documentation changes (if any) are needed to support this PR?:**
Probably not necessary.