Oops. Fixed in #1201363089

I guess I'll add a comment here as well. Changeset #92432812 is the one that added the dual name and references Belgium and Switzerland as examples. Let's wait a few days and change it back maybe?
Also it's weird that openstreetmap.org doesn't put its comments in here. I'm adding this one from JOSM.

This popped up in my RSS reader and I'm inclined to agree with the previous comment. Finland has two official languages. Algeria is another good example.