Yes that last choice is for the “xx” flag
So if you f.i. live in Belgium you have three official languages, German, French and Dutch(Flamish)
But the Belgian flag has no language.
Same for Canada, two languages: French and English, but no language for the Canadian Flag.
Therefor if your country name is NOT listed in the dropdown, you select the last choice “Your country” and the “xx” flag is displayed.
You then find your own country flag, make a copy, rename that copy to xx.svg and your country flag will be displayed.
As long as there is no Norwegian language file, you should copy img/flags/no.svg to img/flags/xx.svg (replacing the Canadian one).
After the browser cache invalidates your Norwegian flag will be in the bottom.
This will be described in the documentation of the April release
Wim
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