SlackAction > Doesn't "url" miss ?

[adriens]

Actually, when i have a look at Slack api (https://api.slack.com/docs/message-attachments#action_fields), i can see the url, while on the slack-webhook code, i only can see

this.name = name;
this.text = text;
this.type = type;
this.value = value;

Slack side :

{
  "text": "<@W1A2BC3DD> approved your travel request. Book any airline you like by continuing below.",
  "channel": "C061EG9SL",
  "attachments": [
    {
      "fallback": "Book your flights at https://flights.example.com/book/r123456",
      "actions": [
        {
          "type": "button",
          "name": "travel_request_123456",
          "text": "Book flights 🛫",
          "url": "https://flights.example.com/book/r123456",
          "style": "primary"
        },
        {
          "type": "button",
          "name": "travel_cancel_123456",
          "text": "Cancel travel request",
          "url": "https://requests.example.com/cancel/r123456",
          "style": "danger"
        }
      ]
    }
  ]
}

[adriens]

hence...should an url member variable be added ?