This is a tad surreal. When recognizing faces, a subtag called "Da" will appear within People/Unknown people" and place all unknown faces inside of it. Now that I think about it, it may have something to so with the user's language. In my language, "Unknown" is spelled "Desconegut", or "Desconegut/da" if you want to refer to both genders. Digikam might treat the "/da" as a subfolder of "Desconegut". If that's the case, it can also be happening to other languages which have a slash sign in that word.
A tag may not contain a "/", if the translation produces this "/", that is a mistake in the translation. Maik
Looks like Maik is right: from l10n-kf5/ca/messages/extragear-graphics/digikam.po: #: libs/database/tags/facetags.cpp:420 #, kde-format msgctxt "The list of detected faces from the collections but not recognized" msgid "Unknown" msgstr "Desconegut/da"
SVN commit 1513977 by jferrer: Proper Catalan translation for tag "Unknown", without slash. M +2 -2 digikam.po WebSVN link: http://websvn.kde.org/?view=rev&revision=1513977
Solved. Thanks for pointing this issue.