update deps + eslint + element as second arg on mount

src/main.ts

@@ -1,3 +1,4 @@
+/* eslint-disable prefer-const */
 import "systemjs/dist/system";
 import "systemjs/dist/extras/amd";
 import "systemjs/dist/extras/named-register";
@@ -16,6 +17,13 @@ const systemJSImport = async (requestUrl: string) => {
   return { component, mount, unmount }
 }
 
+let mainMountElement = document.getElementById('app');
+
+if (!mainMountElement) {
+  mainMountElement = document.createElement('div');
+  mainMountElement.id = 'app';
+}
+
 export default async ({ apps: rawApps, navigations, config, features }) => {
   defineVirtualModule({ navigations, config, features })
 
@@ -38,7 +46,7 @@ export default async ({ apps: rawApps, navigations, config, features }) => {
   }
 
   let { component, mount, unmount } = await getApp()
-  mount(component.default);
+  mount(component.default, mainMountElement);
 
   history.listen(async (location) => {
     if (location.pathname !== prevPathname) {
@@ -46,7 +54,7 @@ export default async ({ apps: rawApps, navigations, config, features }) => {
       unmount()
 
       const nextApp = await getApp();
-      nextApp.mount(nextApp.component.default)
+      nextApp.mount(nextApp.component.default, mainMountElement)
       unmount = nextApp.unmount;
     }
   })