I'm running Firefox 38.0.5 on Windows 8.1, and using the old style (vB 3.x - Fluid) of AAC. I do not experience this problem if I use the new EETech style.

After I've logged out of the forum, the next time I click on Log In I get automatically logged in without having to enter my username or password and am redirected to the home page. If I try to view my Inbox or Alerts, I receive an error and am again redirected. When I navigate to the forum list, I am no longer shown as being logged in, and clicking on Log In repeats this cycle. The only way to end it is to log out from the "semi-logged in" state, and then I can log in again properly.

 

I thought this was fixed, until I realized that the problem is caused by using the old style, not by having "Remember me on this computer" checked as I originally thought. I edited my original post to correct this.

Is anyone else who is using the old style seeing this problem?

 

That just happened to me. Took me about 5 min. and a lot of clicks to get back here.

 

This is fixed now. Thanks, @jrap!