Use the store in the webext options

src/options/App.vue

@@ -11,10 +11,3 @@ export default {
   components: { KeyboardManager },
 };
 </script>
-
-<style>
-html {
-  width: 400px;
-  height: 400px;
-}
-</style>

src/options/main.js

 import Vue from "vue";
+import store from "../store";
 import App from "./App.vue";
 
 /* eslint-disable no-new */
 new Vue({
+  store,
   el: "#app",
   render: (h) => h(App),
 });