At startup it looks like the firebase app is initialized twice

[gmaresca]

Error at startup in browser console

AppComponent_Host.ngfactory.js? [sm]:1 ERROR [DEFAULT]: Firebase: Firebase App named '[DEFAULT]' already exists (app/duplicate-app). at error (http://localhost:4301/vendor.js:167621:21) at Object.initializeApp (http://localhost:4301/vendor.js:167912:13) at AppComponent.ngOnInit (http://localhost:4301/main.js:339:63) at checkAndUpdateDirectiveInline (http://localhost:4301/vendor.js:91654:19) at checkAndUpdateNodeInline (http://localhost:4301/vendor.js:102316:20) at checkAndUpdateNode (http://localhost:4301/vendor.js:102255:16) at debugCheckAndUpdateNode (http://localhost:4301/vendor.js:103277:62) at debugCheckDirectivesFn (http://localhost:4301/vendor.js:103220:13) at Object.eval [as updateDirectives] (ng:///AppModule/AppComponent_Host.ngfactory.js:9:5) at Object.debugUpdateDirectives [as updateDirectives] (http://localhost:4301/vendor.js:103208:21)

It looks like ngx-auth-firebaseui initializes firebase as well from app.module.ts so the initialization in app.component.ts errors out.

You can replicate the error in your live demo looking at the console
http://ngxmatfire.jerouw.nl/home