Comment 4 for bug 2007682

Another instance of duplication:

network:
  bridges:
    br0:
      openvswitch:
        protocols:
          - OpenFlow10
          - OpenFlow11
          - OpenFlow12
        controller:
          addresses:
            - tcp:127.0.0.1:6653
            - tcp:127.0.0.2:6653
      interfaces:
        - nic1
  ethernets:
    nic1: {}

$ tail -n 4 /tmp/fakeroot/run/systemd/system/netplan-ovs-br0.service
ExecStart=/usr/bin/ovs-vsctl set Bridge br0 protocols=OpenFlow10,OpenFlow11,OpenFlow12,OpenFlow10,OpenFlow11,OpenFlow12
ExecStart=/usr/bin/ovs-vsctl set Bridge br0 external-ids:netplan/protocols=OpenFlow10,OpenFlow11,OpenFlow12,OpenFlow10,OpenFlow11,OpenFlow12
ExecStart=/usr/bin/ovs-vsctl set-controller br0 tcp:127.0.0.1:6653 tcp:127.0.0.2:6653 tcp:127.0.0.1:6653 tcp:127.0.0.2:6653
ExecStart=/usr/bin/ovs-vsctl set Bridge br0 external-ids:netplan/global/set-controller=tcp:127.0.0.1:6653,tcp:127.0.0.2:6653,tcp:127.0.0.1:6653,tcp:127.0.0.2:6653