Allow logging back in without leaving CMS admin on session timeout
Currently if your session times out when working in the CMS (for instance if you've disabled the ping feature for security reasons), you just start getting errors.
If you had a lot of work pre-done, it's easy to loose it while trying to log back in.
Instead you should just get a log back in modal pop up over the CMS.
Released in 3.1.7 – http://doc.silverstripe.org/framework/en/changelogs/3.1.7
Damian Mooyman commented