@@ -192,7 +192,8 @@ export default defineConfig([
 		}
 	},
 	{
-		// puppeteer-core is ESM-only (v25+) and is loaded via dynamic import here
+		// puppeteer-core and @puppeteer/browsers are ESM-only and are loaded via
+		// dynamic import here
 		files: ["test/helpers/launchBrowser.js"],
 		languageOptions: {
 			ecmaVersion: 2020
@@ -246,6 +247,22 @@ export default defineConfig([
 			"no-console": "off"
 		}
 	},
+	{
+		// Fetches a browser for the suites that compare against one, from a package
+		// that is ESM-only — so it runs on modern Node rather than the baseline.
+		files: ["tooling/install-firefox.js"],
+		languageOptions: {
+			ecmaVersion: 2022
+		},
+		rules: {
+			"n/no-unsupported-features/es-syntax": [
+				"error",
+				{
+					ignores: ["dynamic-import"]
+				}
+			]
+		}
+	},
 	{
 		// The tool comparisons run on modern Node, not webpack's runtime baseline:
 		// they measure with post-10 APIs (fs.promises, zstd, resourceUsage).
 
@@ -11,11 +11,9 @@ const CACHE_DIR = `${os.homedir()}/.cache/puppeteer`;
  * @returns {Promise<string | undefined>} the executable path
  */
 const installedFirefox = async () => {
-	const {
-		Browser,
-		detectBrowserPlatform,
-		getInstalledBrowsers
-	} = require("@puppeteer/browsers");
+	// ESM-only, like puppeteer-core itself, so it is loaded the same way.
+	const { Browser, detectBrowserPlatform, getInstalledBrowsers } =
+		await import("@puppeteer/browsers");
 
 	const platform = detectBrowserPlatform();
 	for (const one of await getInstalledBrowsers({ cacheDir: CACHE_DIR })) {
 
@@ -1,20 +1,23 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Raj Aryan @aryanraj45
+*/
+
 "use strict";
 
 // Downloads the Firefox the browser suites compare against, into puppeteer's own
 // cache rather than into webpack's dependencies. Safe to re-run: an install that
 // is already there is reported and nothing is fetched.
 
 const os = require("os");
-const {
-	Browser,
-	detectBrowserPlatform,
-	install,
-	resolveBuildId
-} = require("@puppeteer/browsers");
 
 const CACHE_DIR = `${os.homedir()}/.cache/puppeteer`;
 
 (async () => {
+	// `@puppeteer/browsers` is ESM-only, so it is loaded the way puppeteer itself
+	// is rather than with `require`.
+	const { Browser, detectBrowserPlatform, install, resolveBuildId } =
+		await import("@puppeteer/browsers");
 	const platform = detectBrowserPlatform();
 	if (platform === undefined) throw new Error("no browser platform detected");
 	const buildId = await resolveBuildId(Browser.FIREFOX, platform, "stable");