How should Themes handle Internationalization?
Currently, Internationalization is recommended, and if internationalization is incorporated, Themes are required to use theme-slug as a unique textdomain.
What else should be considered? For example:
- If Themes include translation, should all strings be required to be translatable?
- If Themes do not include translation, should any strings be translatable?
- What else should be considered?
In other words: what constitutes best-practice, and what should be avoided, when implementing Theme internationalization?