https://cgit.kde.org/dolphin.git/tree/src/kitemviews/kfileitemmodel.cpp#n2124 The source strings are like: 'Earlier on' MMMM, yyyy In some languages, translators tend to translate single quotes with ‘’ or don't use quotes. Then the translation won't be accepted by GetText. Even I have been translating KDE for seven years, I still made a mistake when translating these strings. The code should be rewritten in a way that can be easier understood by translators. First you string template is: Earlier on %1 %1 is the date string you generated from source string: MMMM, yyyy
see also https://bugs.kde.org/show_bug.cgi?id=401382
Hmm, https://phabricator.kde.org/D18769 initially had the following warning in the context: "Do not replace single quotes with other characters such as «...», otherwise the translation will break." but I don't remember why I removed in the last version of the patch...
Looks like these are now properly explained. https://invent.kde.org/system/dolphin/-/blob/master/src/kitemviews/kfileitemmodel.cpp?ref_type=heads#L2551