@Maik Skoddow,

So in the Tokyo release you can (manually) add new languages once again. In SanDiego we had to restrict it (via requests raised via NowSupport) because we were changing the functionality of the "id" field. 

Previously the length was only 2 chars long, which meant you could only add a "Language". However, there's a lot of use-cases and scenarios to support "locales" which follows the "BCP-47" format.

For those who don't know, is the idea of correlating a Language and a Country. An example is Mexican Spanish as it's not "es" it would be "es_MX", or Austrian German would be "de_AU" for example.

This type of requirement is very important for HR and CSM scenarios, depending on the Organisation and it's scale. Hence you will now see some new features on the [sys_language] once you've upgraded to Tokyo.
Side note - yes an English choice is automatically added to the sys_user.preferred_language field (which drives the language selectors across the instance) to make it easier, and if that choice isn't translated it will always show the English when in other languages just to be safe,

I'll talk more about all of this in my blog closer to the Tokyo release, because there's a whole bunch of interesting things to discuss,

Many thanks,
Kind regards