Dashboard language depending on the browser language

Hi, I'm going to duplicate the dashboard and its pages in another language, which way looks the best for it?
I've tried the module node-red-preferred-language, I connected it on HTTP in module, on the HTTP in I've selected GET and the url of Dashboard http://127.0.0.1:1880/ui, now the modulre returns me the browser language (I guess) which opened the ui, after this should I create a function which changes the page according to the language?

And also, how should I determine when the user as the first time open the ui? If I react each time he produces an http request, the main redirected page will be forced to be loaded, I need it only at first time. Thank you

Any idea? thank you!