How to import only auth from firebase?

Question

JavaScript

There is such a Firebase file:

import * as firebase from "firebase/app";
import "firebase/auth";
import "firebase/database";

var firebaseConfig = {
    apiKey: "smth",
    authDomain: "smth",
    databaseURL: "smth",
    projectId: "smth",
    storageBucket: "smth",
    messagingSenderId: "smth",
    appId: "smth"
};

firebase.initializeApp(firebaseConfig);

export let auth = firebase.auth();
export let database = firebase.database();

What is my idea: I want to import auth into one js file, and database.
The first js file looks like this:

import { auth } from "./firebase.js";
//какой-то код, который работает

The second is like this:

import { database } from "./firebase.js";
//какой-то код, который тоже работает

But at the same time, they have the same file size and it is equal to 400kb. That is, it seems that I am importing all the Firebase modules into each of them.
Here is the webpack config if anyone is interested:

const path = require("path");

module.exports = {
  entry: {
        auth: "./source/js/auth.js",
        listRequests: "./source/js/listRequests.js",
    },
  output: {
    filename: "[name].bundle.js",
    path: path.resolve(__dirname, "source/js")
  },
  devServer: {
     contentBase: path.join(__dirname, 'source/'),
    port: 3000
  }
}

So the question is how to import only what I need? Because even when I import only the function I need, everything else flies into the JS file, which is why the size of the JS file becomes, well, disproportionately huge.