If anyone knows anyone at #Tailscale, I'd like a quiet word (they've closed their user-facing forum)

Machine A has subnet 10.0.0.0/23
Machine B, dead for a few months, happens to advertise subnet 10.0.0.0/23 in the admin panel.

tailscale up --accept-routes on Machine A seems to kill networking.

What?

Your local machine subnet should always be a higher priority, shouldn't it?