Quote fromThat and the site detects you as being idle if you spend a period of time not doing anything "actively", meaning posting, searching, hittin da buttenz randomely etc.
I agree with Paladin88! It seems your login session expires, so you have to login again! It happens to me from time to time! If you're inactive for some time, then it will happen!
I stay logged on for hours sometimes when I forget to log off and I'm obviously not doing anything and it hasn't happened to me.
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