Angularfire2 on Ionic3

I’m trying to use Angularfire2 on an Ionic3 app.

When installing it npm install angularfire2 , I get a deprecation warning:

npm WARN deprecated angularfire2@5.2.1: AngularFire has moved, we're now @angular/fire .

But if trying to install the new @angular/fire npm install @angular/fire I see that every version requires an @angular/core >= 6.0.0 -which is greater than the Ionic3 supported on (i.e. “5.2.11”).

So, my question is how can I make use of a non-deprecated angularfire2 lib on Ionic3?

(You can also find this question on SO: https://stackoverflow.com/questions/57739589/angularfire2-ionic3?noredirect=1#comment101918279_57739589 )