If admin is set to a non-english language, reloading using the terminal and "reload all" or the Url parameter fwreinit=true forgets the language. It always switches back to english.
In addition, if switching from english to a non-english language in the backend, the system always redirects to the site tree.
Currently developing in a e.g. german admin is very annoying. Example scenario:
1. Switch to german
2. go to page currently working on
3. perform code changes
5. start at 1. again
So the 2 small improvements would be:
stay on the current page on language switch
use the last used language after app re-init