I followed <https://fontawesome.com/how-to-use/on-the-web/using-with/vuejs>.

But when use it like:

```
import { library } from '@fortawesome/fontawesome-svg-core'
import { faBars } from '@fortawesome/free-solid-svg-icons'
import { faTwitter, faFacebook, faStackOverflow, faGithub } from '@fortawesome/free-brands-svg-icons'
import { FontAwesomeIcon } from '@fortawesome/vue-fontawesome'

...

library.add(faBars, faTwitter, faFacebook, faStackOverflow, faGithub )
Vue.component('font-awesome-icon', FontAwesomeIcon)

...

<font-awesome-icon icon="twitter" class="icon alt"/>

```

Got: 

> 
> Could not find one or more icon(s) {prefix: "fas", iconName: "twitter"}
> 
> 
>