Signal Messenger and Selector

Tags: #<Tag:0x00007fc41ca3d6c0> #<Tag:0x00007fc41ca3d4e0>

Hi,

I would like to create a blueprint to receive notification either with mobile_app or with signal_messenger.
Both notifications are working however I am not able to find the right selector in the blueprint input that will restrict the choice.

In reality I am not even able to find a selector that is able to select signal_messenger.

Here is my current blueprint that works well, but the notify input selector is not.

blueprint:
  name: Light Notification
  description: Send a notification when a light is switch on
  domain: automation
  input:
    light_entity:
      name: Entity
      selector:
        entity:
          domain: light
    notify_device:
      name: Device to notify
      description: Device that will receive the notification
      selector:
         entity:
           domain: notify

trigger:
  - platform: state
    entity_id: !input "light_entity"

action:
   service: "notify.signal"
   data:
      message: "plop"

Thank you in advance,