Not sure it has been made clear on this thread (but it has been mentioned in some others), but connections will timeout -- pretty quickly, actually -- already.
Fire up DWAdmin and watch the license screen. I just started a DocuWare web client session at 8:38, and my license use showed up, saying it would expire at 9:08, a reservation of 30 minutes.
I left the tab open in my web browser but did not do anything with the session. I used other browser tabs as usual.
I kept checking my expiration time for my license, and at 8:48 (10 minutes after initial license use), the expiration time changed to 8:50, just 2 more minutes. After 8:50, I was no longer using a license.
In summary, it looks like when a session goes idle, a license will only be in use for 12 more minutes. Ten minutes for the idle-detection timeout and then 2 minutes more for some built-in grace period DocuWare keeps in play to cushion session restarts (I don't care for it -- an explicit log off should immediately free the license, in my opinion). Overall, though, 12 minutes isn't really that long, and we have never had an issue running only 20 licenses for over 75 named, semi-active users.
An additional note -- even after my license usage had disappeared, I did a search in the DocuWare web page still displaying in my browser and it ran without me needing to log in again. So, being timed-out isn't even really a timeout, at least not in that it forced a re-logon.
All of this works the same way for Platform Service use: initial license grab is for 30 minutes, after 10 minutes of inactivity the expiration switches to 2 minutes from the current time, and even an explicitly called "LogOff" request still keeps the license in use for 2 more minutes.
Is a twelve-minute timeout something you can work with? Are you seeing something different in your license usage? I am running 6.11 on-premise with all the latest hotfixes and patches applied.