Merge pull request mozilla#17547 from timvandermeij/remove-dns-resolv…

…er-workaround

Remove DNS resolver workaround from the test framework

test/test.mjs

@@ -20,7 +20,6 @@ import {
   downloadManifestFiles,
   verifyManifestFiles,
 } from "./downloadutils.mjs";
-import dns from "dns";
 import fs from "fs";
 import os from "os";
 import path from "path";
@@ -34,21 +33,6 @@ import yargs from "yargs";
 
 const rimrafSync = rimraf.sync;
 
-// Chrome uses host `127.0.0.1` in the browser's websocket endpoint URL while
-// Firefox uses `localhost`, which before Node.js 17 also resolved to the IPv4
-// address `127.0.0.1` by Node.js' DNS resolver. However, this behavior changed
-// in Node.js 17 where the default is to prefer an IPv6 address if one is
-// offered (which varies based on the OS and/or how the `localhost` hostname
-// resolution is configured), so it can now also resolve to `::1`. This causes
-// Firefox to not start anymore since it doesn't bind on the `::1` interface.
-// To avoid this, we switch Node.js' DNS resolver back to preferring IPv4
-// since we connect to a local browser anyway. Only do this for Node.js versions
-// that actually have this API since it got introduced in Node.js 14.18.0 and
-// it's not relevant for older versions anyway.
-if (dns.setDefaultResultOrder !== undefined) {
-  dns.setDefaultResultOrder("ipv4first");
-}
-
 function parseOptions() {
   const parsedArgs = yargs(process.argv)
     .usage("Usage: $0")