function run_test() { do_load_manifest("data/chrome.manifest"); if (typeof Intl !== "object") { dump("Intl not enabled, skipping test\n"); equal(true, true); return; } let mainThreadLocale = Intl.NumberFormat().resolvedOptions().locale; let testWorker = new Worker("chrome://locale/content/intl_on_workers_worker.js"); testWorker.onmessage = function (e) { try { let workerLocale = e.data; equal(mainThreadLocale, workerLocale, "Worker should inherit Intl locale from main thread."); } finally { do_test_finished(); } }; do_test_pending(); testWorker.postMessage("go!"); }