About HTTPv1 notificaion message

[H.Kura]

Dear Team,

We are using Firebase HTTPV1 and i am under spark plan(No cost)

We set as followings message for notificaiton Json format:
      "title": "notification",
      "action": "OPEN_APP",
      "channel_id": "notification",
      "sound": "default"

The "action" parameter is not specification in HTTPV1,
what happens the notification clicked？

Originally, you should use the "click_action" parameter as per the specifications, but
In the Regacy API, the application we developed was launched by setting the "action" parameter.

Is the "action" parameter a valid parameter in HTTPv1 ?


Sincerely,
H.Kurata