Webostv notify platform: Does alternative icon in notify.lg_webos_tv service work?

The documentation shows:

automation:
  - alias: "Front door motion"
    trigger:
      platform: state
      entity_id: binary_sensor.front_door_motion
      to: "on"
    action:
      service: notify.livingroom_tv
      data:
        message: "Movement detected: Front Door"
        data:
          icon: "/home/homeassistant/images/doorbell.png"

but what is not clear is whether the path to the icon is from HA’s perspective or the tv’s. I am presuming it’s from HA’s but this does not work:

service: notify.lg_webos_tv_uj7700
data:
  message: "May is at the front door"
  data:
    icon: "/local/images/may_yang.png"

Has anyone been able to specify a notification icon?