Hello Zac Morris, you still may consider installed systemd-coredump and when it happens again provide the complete lines reported by journalctl related to the crash.
I, as I said not deeply involved in dnsmasq and just trying to collect some information, tried to replicate your configuration, but in my case dnsmasq then crashes already at start. I have created these files just as empty ones: /etc/dnsmasq.d/hosts/hosts.block /etc/dnsmasq.d/hosts/hosts.local /etc/dnsmasq.d/dhcp-hosts And appended to /etc/dnsmasq.conf: conf-file=/etc/dnsmasq.d/lan.conf If I understand you right, you download e.g. https://raw.githubusercontent.com/EnergizedProtection/block/master/unified/formats/dnsmasq.conf and then put it to /etc/dnsmasq.d/hosts/hosts.block.dnsmasq.conf Kind regards, Bernhard