Resolved
Reported for: CMS Beta Package 3.1.8-b4
Overview of the issue
Admin UI changes language when switching from admin language switcher.
When switching language using the admin language switcher, the whole user interface, in the admin area, changes to the selected language.
The normal behavior is that only the content must switch to the selected language, whilst the user interface must stays to the default language, or the language selected in the user profile settings.
Workaround
Fixed in 3.1.8