Ionic 2 RC.0 and Firebase (not angularFire)

I have switched from:
import * as firebase from 'firebase';
to
import firebase from 'firebase';

which eliminated the error messages regarding ‘auth’, ‘eval’ etc.

However, I am still seeing the following error message:
Uncaught TypeError: Cannot read property 'navigator' of undefined

when attempting to initialize firebase under the constructor.

Was anyone able to overcome this error?