Huh, how bizarre. It doesn't happen in all languages – of the languages I've checked, these were fine:

• nb, de, fr, nn, zh-hans, zh-hant, ar

But these were the same as English:

• sw, zh, ig, he, ur (sw and ig don't have a translation for it in TWN, so that makes sense. But zh should fall back to zh-hans, and he and ur have translations).

There doesn't seem to be anything systematic to it… 🤔

I've added a request onwiki to hopefully fix it.

The other string doesn't seem to exist in TWN, but maybe it got changed or something in the past? Anyway, hopefully my suggested edit will fix things!