How to get browser language in ServiceWorker?

Question

How to get browser language in ServiceWorker?

navigator.language || navigator.userLanguage; //not work

Answer 1

This should work now according to the spec.

If your users are using an older version of Chrome, you have to rely on the language read from the global (regular) window.navigator.language and pass it to the Service Worker via navigator.serviceWorker.controller.postMessage. Here is the old Chrome tracking bug.

Alternatively, you can try reading Accept-Language header from your Requests in fetch event handler - event.request.headers.get('Accept-Language') - although it didn't work for me for some reason.