diff --git a/Optional-Hardening.md b/Optional-Hardening.md
index 65a36fb..50faa7f 100644
--- a/Optional-Hardening.md
+++ b/Optional-Hardening.md
@@ -70,7 +70,7 @@ user_pref("browser.sessionstore.privacy_level", 2);
       * Go to `☰` *→ Settings → Privacy & Security → DNS over HTTPS → Manage Exceptions*
 ```
 // PREF: enforce DNS-over-HTTPS (DoH)
-user_pref("network.trr.uri", "https://freedns.controld.com/x-hagezi-proplus");
+user_pref("network.trr.uri", "https://dns.quad9.net/dns-query");
 user_pref("network.trr.mode", 3);
 user_pref("network.dns.skipTRR-when-parental-control-enabled", false);
 ```