Multilanguage interface in single language wiki

I would like that my users could choose the language of the web interface without having a multilanguage setup. It’s more a matter of taste because some users prefer the english interface.
I changed the forceSupported to 0 while keeping multilingual mode as No

xwiki.language.forceSupported=0

Still, I can’t see the language picker in the interface, is this possible?

xwiki.language.forceSupported

The point of this property is only allow one of the configured supported languages but not enabling multi language means using the configured default language all the time.

What you want to do does not really exist right now also I have a hard time understanding how a user could chose a language if you don’t want to display that choice. Only take into account the browser locale ?

Basically, the issue is that the locale I am using (catalan) is still not 100% complete (I added some strings but there are some still missing), and some users prefer to see it in english at least until is more complete. Also I’d like to have the superadmin to see the interface in english because that way is easier to follow configuration guides / report issues, etc.