It changes the language on the fly, but not for already running applications. You need to quit and restart the applications.

MorphOS never did and it is not worth the time implementing such thing. Just think about Ambient. It needs to ensure all applications are gone, before it even can restart. The result would be the same we have when a custom window is on a public screen and you want to change a resolution. "Please close all windows, so the new language can be set." I don't want this mess.

The only time you can see a translation change on the fly is when MorphOS gets installed and you select a different language. This only works, because all the UI modules are libraries and the entire thing gets restarted. That is why everything is flickering away and returns. Basically the install process get restarted.

Changing at runtime is a potential risk of dealing with old pointers and stuff. As a result an application may crash due to a forgotten text pointer. It is simply not the way to go. Programms are far to complex these days and I know several start up code pieces in my applications that would require a rewrite, just to work more than once with different catalogs.

I cannot remember when I changed the system language. Must be years ago.