`require` is not defined using @xdn/svelte/Prefetch component

I am attempting to import the XDN Prefetch component using:

<script>
  import { Prefetch } from '@xdn/svelte';
  import Rating from '../../components/Rating.svelte';
  
  export let products = [];
</script>

On the client, I get the error: Uncaught (in promise) ReferenceError: require is not defined.

Inspecting the source, the error occurs on this line:

<script>
  import { onMount } from 'svelte';
  const { prefetch: doPrefetch } = require('@xdn/prefetch/window')
                                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  ...
</script>

I suspect this is related to the mix of import and require statements in addition to using Rollup bundler for my Sapper project. Changing this to an import seems to resolve the error. For reference, this is my config:
rollup.config.js

import path from 'path';
import resolve from '@rollup/plugin-node-resolve';
import replace from '@rollup/plugin-replace';
import commonjs from '@rollup/plugin-commonjs';
import url from '@rollup/plugin-url';
import svelte from 'rollup-plugin-svelte';
import babel from '@rollup/plugin-babel';
import { terser } from 'rollup-plugin-terser';
import config from 'sapper/config/rollup.js';
import pkg from './package.json';
import sveltePreprocess from 'svelte-preprocess';

const mode = process.env.NODE_ENV;
const dev = mode === 'development';
const legacy = !!process.env.SAPPER_LEGACY_BUILD;

const preprocess = sveltePreprocess({
	postcss: true,
});

const onwarn = (warning, onwarn) =>
	(warning.code === 'MISSING_EXPORT' && /'preload'/.test(warning.message)) ||
	(warning.code === 'CIRCULAR_DEPENDENCY' && /[/\\]@sapper[/\\]/.test(warning.message)) ||
	onwarn(warning);

export default {
	client: {
		input: config.client.input(),
		output: config.client.output(),
		plugins: [
			replace({
				'process.browser': true,
				'process.env.NODE_ENV': JSON.stringify(mode)
			}),
			svelte({
				dev,
				hydratable: true,
				emitCss: true,
				preprocess: [preprocess],
			}),
			url({
				sourceDir: path.resolve(__dirname, 'src/node_modules/images'),
				publicPath: '/client/'
			}),
			resolve({
				browser: true,
				dedupe: ['svelte']
			}),
			commonjs(),

			legacy && babel({
				extensions: ['.js', '.mjs', '.html', '.svelte'],
				babelHelpers: 'runtime',
				exclude: ['node_modules/@babel/**'],
				presets: [
					['@babel/preset-env', {
						targets: '> 0.25%, not dead'
					}]
				],
				plugins: [
					'@babel/plugin-syntax-dynamic-import',
					['@babel/plugin-transform-runtime', {
						useESModules: true
					}]
				]
			}),

			!dev && terser({
				module: true
			})
		],

		preserveEntrySignatures: false,
		onwarn,
	},

	server: {
		input: config.server.input(),
		output: config.server.output(),
		plugins: [
			replace({
				'process.browser': false,
				'process.env.NODE_ENV': JSON.stringify(mode)
			}),
			svelte({
				generate: 'ssr',
				hydratable: true,
				dev,
				preprocess: [preprocess],
			}),
			url({
				sourceDir: path.resolve(__dirname, 'src/node_modules/images'),
				publicPath: '/client/',
				emitFiles: false // already emitted by client build
			}),
			resolve({
				dedupe: ['svelte']
			}),
			commonjs()
		],
		external: Object.keys(pkg.dependencies).concat(require('module').builtinModules),

		preserveEntrySignatures: 'strict',
		onwarn,
	},

	serviceworker: {
		input: config.serviceworker.input(),
		output: config.serviceworker.output(),
		plugins: [
			resolve(),
			replace({
				'process.browser': true,
				'process.env.NODE_ENV': JSON.stringify(mode)
			}),
			commonjs(),
			!dev && terser()
		],

		preserveEntrySignatures: false,
		onwarn,
	}
};

That is strange. Not sure why prefetch is being loaded with a require instead of an import there. @mark.brocato any ideas why this was done?

https://github.com/moovweb/xdn/blob/2ba902fba724ae01e31fb06b7249120b71ae4ffe/packages/svelte/src/Prefetch.svelte#L3