I'm using firebase for the first time in vue.js.
After installing firebase using npm, I added it to main.js as follows.

```
//main.js
import { createApp } from "vue";
import App from "./App.vue";
import Router from "./router.js";
// bootstrap
import "bootstrap/dist/css/bootstrap.min.css";
import "bootstrap";

// firebase
import firebase from "firebase";

// For Firebase JS SDK v7.20.0 and later, measurementId is optional
const firebaseConfig = {
  apiKey: "",
  authDomain: "",
  projectId: "",
  storageBucket: "",
  messagingSenderId: "",
  appId: "",
  measurementId: "",
};

firebase.initializeApp(firebaseConfig);

createApp(App).use(Router).mount("#app");

```

And this is package.json

```
  "dependencies": {
    "bootstrap": "^5.1.3",
    "core-js": "^3.6.5",
    "firebase": "^9.6.4",
    "vue": "^3.0.0",
    "vue-carousel-card": "^2.0.0",
    "vue-router": "^4.0.12",
    "vue3-carousel": "^0.1.35"
  },

```

If I add firebase and run serve it like this, an error that says firebase cannot be found is output.

```
This dependency was not found:

* firebase in ./src/main.js

To install it, you can run: npm install --save firebase

```

May I know the cause and solution of this?
Thank you always.