Date format localization is currently handled by the system module, which provides its own UI not consistent with the rest of the localization system and requires features -config translation- provided by locale module. This causes multiple issues ranging from usability to some ugly workarounds to update localized formats, to hidden functional dependencies (and maybe the feature being in the wrong module).
- Move Date format localization to locale module (
- Use the right API, aka config translation, to update and handle date format localization.
- Integrate the UI with Regional and Language / User Interface translation.
- Make it consistent with interface translation respecting locale settings like 'translate english'.
While there are multiple related issues, none of them is trying to address the problem as a whole, but just a few symptoms/sides of it.
The main patch, that needs review and UI discussion,
- click through the UI and figure out the features, a full UI / feature comparison of D7 and D8, so we know what regressed in fact.