I noticed that if you're not logged in and you try to reply to a thread, you can log in and it takes you right to the reply. It looks like the login form save the referring page, but how does it doe this? Does it rely fully on HTTP_REFERER or is there a backup plan if this doesn't work?
Anyone know?
seems to me it saves the page or id or whatever in the URL. Then it references that.
It's the same as phpBB, SMF, vB, IPB.... they all handle it via the URL.