[[rw]]

Exactly how is "rw" an "unverified ISO 639-1 code"?

Is Kinyarwanda. Of course. What's the issue?

"Use-mention distinction", apparently the codes are always mentioned, never used. That's not actually the case, it's more than with 6000 codes you need 18000 citations, and surprisingly enough, nobody's been able to find the necessary 18000 citations in a month.

@RU, see WT:BP#ISO language codes (again) for the most recent discussion (which links back to others you might not have seen).