Session flush / RainLab User Logout

Hi,
i have a little bit concern about RainLab.User plugin, because on each user logout/signout was cleared session, but not only for frontend, but for backend too.

User on backend is logged-in, but any form-based token is at that point invalid.

Steps to reproduce
Log-in to frontend as RainLab.User

Open something on backend (like Backend authenticated user), and try to change something (without save or anything)…

Logout from frontend as front-end user…

On backend try to save previously oppened document or whatever…
U got info about invalid token…