I am trying to reduce the bundle size of th Javascript bundle created by Webpack. So I only want to include specific scripts into the bundle under certain conditions.

E.g. this code should only add login.js when the user actually is on the login page /login. On all the other pages, it should not be added:

type Module = {
    default: () => void;
}

const resolveModule = (modulePromise: Promise<Module>) => {

    modulePromise.then((module: Module) => {
        if (typeof module.default === 'function') {
            module.default();
        }
    })
 
}

document.addEventListener('DOMContentLoaded', () => {

   switch(window.location.pathname.split('/')[1]) {
      case 'login':
        resolveModule(import('./login.js'));
   }
});

The problem is, Webpack creates a bundle that includes login.js all the time. How can I prevent that?