Messed around with official name (P1448) in Glittertind (Q397876) and realized that official names are often given in macrolanguages. The name Glittertinden is now listed as nb but should be nn. I think this is quite common to avoid creating several closely related names. In Norwegian that means that monolingual text must support no in addition to nb and nn.
Macrolanguages are also called metalanguages.