1. Choose Libre-DoT server: blahdns.de, snopyta.org, dismail.de
2. sudo nvim /etc/systemd/resolved.conf:
  
DNS=116.202.176.26:854#dot.libredns.gr
FallbackDNS=127.0.0.1 ::1
Domains=~.
DNSOverTLS=yes
  
3. Remove auto-dns in Network Settings and insert resolv ip -> 127.0.0.53
4. sudo systemctl restart systemd-resolved.service && sudo service NetworkManager restart

# Check with: DoT: sudo ngrep port 853 / DNS: sudo ngrep port 53
