Kurt, it doesn't work. I did everything you suggested. Logged in to the forums, did a bit of (web!) surfing, left my Mac for a couple of hours, went to the forums, and hey presto! Yes, I had to login - again!
It seems to me that if I don't have any activity on the forums for around 30 minutes, then I have to re-login. I'm not the only one who is experiencing this.
It's a major pain. For example, if I reply to a forum notification email, I am taken to the thread, but I am not signed in. So, then I go to the login page, and my place on the relevant thread is lost as I am taken to the standard user-logged in page. I then have to go back to the email, and re-link from there.
If this is a rant, then I'm sorry, but, this whole thing puts me off using these forums, which is a shame as I have enjoyed being here for a number of years now.
I would really like to know who to contact regarding this issue.
Any ideas?