Angular app does not load - no errors on browser

I created one simple angular application. Webpack compiled successfully. localhost:4200 opened my application. Cool.

To host it on firebase, I tried to install firebase@4.2.0 and angularfire2@4.0.0-rc.1 but I got a self signed certificate error since I'm behind my org firewall.

After this, my app stopped working and I don't see any error on browser too. It just doesn't load. How do I debug this? Not just this app, my other angular apps also stopped working. I even tried creating a new app and it doesn't load as well. All of them compile successfully when I run ng serve command.

My main.ts file:

import { enableProdMode } from '@angular/core';
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { AppModule } from './app/app.module';
import { environment } from './environments/environment';

if (environment.production) {
  enableProdMode();
}

platformBrowserDynamic().bootstrapModule(AppModule);

My index.html:

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <title>SampleApp</title>
  <base href="/">

  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="icon" type="image/x-icon" href="favicon.ico">
</head>
<body>
  <app-root></app-root>
</body>
</html>

app component:

import { Component } from '@angular/core';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  title = 'app';
}

I guess that some libraries were corrupted after firebase installation attempt and need to be reinstalled/repaired.

Please suggest how to get to the root cause and fix it.