Yeah it's definitely new, and can't be disabled as a free user. I don't even really mind that so much if it was made known that is the reason for the annoyance. There's nothing in the popup or settings to indicate it only affects free users, in fact there is a timeout setting in advanced that suggests we can turn it off, but that doesn't affect it which i find counter productive. I didn't see anything in the change notes about this, and one of the things I hate is undocumented features lol.
I'm not a paying user so I can't complain about the added timeout, it's an annoyance intended to get people to start paying, makes sense. I just wish it was more upfront about it, like something in the notice that said we'd stop doing this if you paid us ^_*
I don't need most of the features of the latest version, and it's not that I use team viewer all day but I prefer to just stay logged in with a minimized window so I can look at a remote PC once in a while and its annoying to keep having to connect back to it all the time. So i'll probably just downgrade back to v10, I don't use it enough to pay for it or need the new version enough to suffer the session timeout change. It does it even if i'm actually using the session, which it's hard to think of something more annoying when you are in the middle of something.