LXC not resolving after installing Docker

I have ~15 LXC containers each with netplan manually configured (including DNS). I recently installed Docker for the first time and immediately lost name resolution within all LXC containers. So from within an LXC:

# works
ping google.com
# ping: google.com: Temporary failure in name resolution

DNS works fine in Docker containers and host.

Any ideas?

Yeah, Docker has a bit of a tendency to mess with your firewall and block forwarding of all traffic except its own…