✨ (header) back button if app installed

src/App.vue

@@ -20,6 +20,17 @@
             </div>
           </online-view>
         </router-link>
+        <app-installed class="navbar-item">
+          <template v-slot:app-installed>
+            <a href="#" @click="back">
+              <img
+                class="back-icon"
+                src="./assets/icons/baseline_arrow_back_white_48dp.png"
+                alt="back"
+              />
+            </a>
+          </template>
+        </app-installed>
         <span class="vaquant-title" :class="{ visible: shadow }">{{
           title
         }}</span>
@@ -73,13 +84,15 @@ import { Action, Getter } from 'vuex-class'
 import IUser from '@/models/IUser'
 import { COFFEE_LINK } from '@/utils/constants'
 import OnlineView from '@/components/OnlineView.vue'
+import AppInstalled from '@/components/AppInstalled.vue'
 
 @Component({
   directives: {
     ClickOutside
   },
   components: {
-    'online-view': OnlineView
+    'online-view': OnlineView,
+    'app-installed': AppInstalled
   }
 })
 export default class App extends Vue {
@@ -114,6 +127,10 @@ export default class App extends Vue {
   public hideMenu(): void {
     this.menuOpen = false
   }
+
+  public back(): void {
+    window.history.back()
+  }
 }
 </script>