I recently discovered that systemd supports drop-in config files so I'd recommend putting the changed settings into something like /etc/systemd/resolved.conf.d/

I recently discovered that systemd supports drop-in config files so I'd recommend putting the changed settings into something like /etc/systemd/resolved.conf.d/disable-stub.conf. That way your package manager isn't upset that files it controls are modified. I wrote a personal blog post about this (https://www.turek.dev/posts/disable-systemd-resolved-cleanly/ https://www.turek.dev/posts/disable-systemd-resolved-cleanly...) to try to help people out.