I tried adding 'accept-ra: no' to the YAML, and tried the workaround in bug #1736975 (manually creating a .network file in /etc/systemd/network) and neither prevented the stall. However, after two minutes, networkd gives up and allows the system to continue booting - and the bridge exists.
I tried adding 'accept-ra: no' to the YAML, and tried the workaround in bug #1736975 (manually creating a .network file in /etc/systemd/ network) and neither prevented the stall. However, after two minutes, networkd gives up and allows the system to continue booting - and the bridge exists.