Version info

angular/fire: 5.1.2
firebase: 5.11.0

How to reproduce these conditions

@angular/fire v5.1.2 seems to doesn't play well with firebase v5.11.0. when these versions are installed I face the following error when I start my (Ionic) app:

[ng] ERROR in node_modules/@angular/fire/firebase.app.module.d.ts(17,22): error TS2420: Class 'FirebaseApp' incorrectly implements interface 'App'.
[ng]   Property 'performance' is missing in type 'FirebaseApp'.

Downgrading firebase to v5.10.1 fix the issue. I guess the property 'performance' was added as a mandatory field in the last version of firebase.