Sometimes when I idle around on the site, I get signed out and can't sign back in unless I request that my password be changed. I don't know what's wrong. Should I just start exiting the windows when not in use? I sometimes think that someone has gotten into my account but when I request for a password change, everything is fine afterwards. Nothing is changed.

This type of thing is best handled by a ticket. Staff can check your account to see if anything weird is going on.
I will often have a window/tab open, usually several and wonder off to another site for up to a couple of hours. Come back and everything is fine. If I do happen to get logged out (happens every few weeks), I just get the regular login screen, enter my info and everything is fine. So what's happening to you is not normal.
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