First of all, thank you very much @softworks ! Great Job!
I use Hayden template and injected the script with no problems whatsoever. The Nav-Items of the respecitve other language become invisible.
However, when I injected the CSS (which as far as I understood styles the choose-language-button) nothing happens. So there is no way for a visitor to change the language.
any Idea what I have done wrong?
Sadly I don't have any solution. However, I am using Hayen, too, and wonder what changes you made to the above mentioned CSS-Snipet to make the Language-Button appear. Would you mind to share your CSS-Code?