It's not a major issue,
bu when I'm using IE once I enter a thread I can no longer 'go back' to the main page, I have to use the link at the top/bottom of the page, although I can still 'go back' within the thread itself)
whatever has caused this has happened today as far as I can tell
(Chrome and Firefox do not have the issue)
I can adjust my behaviour or browser if necessary, ( but if it's a simple fix it would be nice to have the normal back button behaviour back

)