[Решено] Language switcher: How can I display the non-current language by default?

I have a site with main language German. The language switcher shows the current language by default. How can I change this so that someone who lands on the German site immediately sees that there's an English version available without having to click on Deutsch to open the language switcher menu.
I think I found the setting where this could be changed (in the language switcher settings), but it's not possible to deselect the checkbox as it's greyed out.