I'm trying to use Angular 4 with Plunker and I can't manage to add a new component. The URL is: https://plnkr.co/edit/1umcXTeug2o6eiZ89rLl?p=preview

I've just created a new component - mycomponent.ts - with the minimum of declarations. Then, in app.ts, I'm adding the importing declaration:

import {MyComponent} from "./mycomponent";

and add the component in the declarations array within the @NgModule decorator:

 declarations: [ App, MyComponent ],

This last bit breaks it and returns a 404 XHR error. So far I just played with changing the import declaration ("./" or not), inline/URL template for the component template, chrome/firefox browsers but nothing works so far. I'm inclined to think it's Plunker's fault :S