Color names for Clean Frames HTML export theme are not translatable. See the entries "Caption_*" in data/htmlgallery/themes/cleanframes/cleanframes.desktop, e.g.: Pink, Blue, Lavender, ...
The text is not translatable because off desktop file field use "_" as separator and this one is not permit in desktop standard. I replaced this character by "-" everywhere... This will be better. I'm waiting than desktop files are re-parsed by i18n script to see if this behavior change Gilles Caulier
These captions are still missing from the translation catalog templates (digikam.pot or digikam._desktop_.po).
I check with French and German translations under MacOS, and both are "Clean Frames" theme translated in the plugin now. I close this file now. Gilles Caulier