Why Webpack swallows Node execution?

Consider the following example:

const vm = require('vm');
const Rx = require('rxjs');

const sandbox = { Rx, setTimeout, console };
const code = `
  observable = Rx.Observable.create(observer => {
    setTimeout(() => {
      console.log("Emitting 1");
      observer.next(1);
    }, 1000);
  });
`;

vm.runInNewContext(code, sandbox);

console.log('Subscribing');
sandbox.observable.subscribe(x => console.log(`Received ${x}`));

When I run this example in Node (v6.3.0), I get the following output as expected:

Subscribing
Emitting 1
Received 1

However, when this code runs through Webpack, I get only:

Subscribing

See here.

Any ideas what's going on here, and how to get the expected behavior when using Webpack?

via Misha Moroshko