Weave net empty flows for OpenvSwitch

Question

I have 2 containers c1/c2 on 2 separate hosts and I am running Weave Net docker plugin with multicast and fastdp enabled.

Both containers can communicate fine on the underlay network both in unicast and multicast packets.

But weave report show :

"OverlayDiagnostics": {
            "fastdp": {
                "Vports": [
                    {
                        "ID": 0,
                        "Name": "datapath",
                        "TypeName": "internal"
                    },
                    {
                        "ID": 1,
                        "Name": "vethwe-datapath",
                        "TypeName": "netdev"
                    },
                    {
                        "ID": 2,
                        "Name": "vxlan-6784",
                        "TypeName": "vxlan"
                    }
                ],
                "Flows": []
            },

There is no openflows configured for the ovs datapath.

I have mapped the network topology of what I know of Weave net :

Network topology

I don't understand how the packets are routed from the veth Weave-Datapath to the vxlan interface doing its thing.

It seems Weave is intercepting packets

Packet capture and injection use the "datapath" device, via "router/fastdp.go:fastDatapathBridge"