more FA5 stuff with small related refactoring

src/components/chat_panel/chat_panel.js

@@ -1,4 +1,10 @@
 import generateProfileLink from 'src/services/user_profile_link_generator/user_profile_link_generator'
+import { library } from '@fortawesome/fontawesome-svg-core'
+import { faBullhorn } from '@fortawesome/free-solid-svg-icons'
+
+library.add(
+  faBullhorn
+)
 
 const chatPanel = {
   props: [ 'floating' ],