Who need to install qt-translation packages?

[<c.buhtz@posteo.jp>]

Hello,

I'm upstream maintainer of "backintime" but also interested in Debian
specific packaging.

A question came up about dependencies in the context of the Qt
translations.

If Qt is installed does it recognize the current systems locale and
install the translations for it?

When having a package (e.g. "backintime-qt") using Qt translations
(only for standard GUI elements like buttons) should this package
depend on a qt-translation package? "backintime-qt" does directly
depend on "python3-pyqt5".

https://packages.debian.org/unstable/backintime-qt

Thanks for advice.
Christian Buhtz