Thank for replying.
We need this for a 3rd party Joomla chat, collaboration, and conferencing software app which is integrated with CB and operates very stable.
However they have their own language management for UI and transliteration services.
To get their UI in the language a user is working with in CB profile, language_code has to be set as a cookie to share this info.
Yes, this might be not an issue for CB and of course it is not an error generated.
Were just figuring out appropiate way to set cookie and where to place code required.