I have two different computers that I access PF with and lately, the newer one isn't marking threads as read unless I reload the page. I haven't made any changes to my browser settings on either browser before this started. Was something changed about two weeks ago that might be causing this? The browser with the problem is Firefox 15 on Windows 7. The one that hasn't been affected is Firefox 3 on XP. I've tried a number of things including turning off all browser caching. No luck.