If your firebase database rules are set to this:
{
"rules": {
".read": "auth == null",
".write": "auth == null"
}
}
Then you can safely ignore the warnings.
You can also disable email warnings by doing the following:
Goto this link: https://console.firebase.google.com/u/0/subscriptions/overview
Select your project again and disable email for Firebase insecure rules and expiring rules.
Done.
