Does anyone know where this information is stored and whether it can be undone? On some forums this information sometimes gets reset and I end up not seeing any new posts being highlighted. They are all marked as read and I'm not sure why this is. Forums.mydigitallife.info is one of those forums where this happens quite a lot. I don't see this problem at all with the Wilders forums.
First guess .... and it is just a guess .... your browser cache ? .... cookies ? Maybe a difference in site-specific settings , whitelists , cookie policy etc .... try comparing these for the two sites you mention. What browser and extensions are you using ?
The only extension that that I have that might be related to the problem is Self-Destructing Cookies, but I have that set to never self destruct for forums.
Auto-mark as read seems to be an inactivity time-based (DB or Cookies) option that some forums use, which to me gets quite annoying after a while. Apparently this option is used to be less server intensive. Maybe LowWaterMark can shed some light on how this option is used here at Wilders, where I don't see this problem
Long ago, early vBulletin 3.0, I think, we also had the same problem here. The only option for storing thread read markers was cookie based. And, there were all kinds of circumstances where you'd either lose all markers and nothing looked unread, or, everything would suddenly look unread. I hated that, too. But, since vBulletin 3.5 and on, and now in XenForo, the option became available to store the markers in the database, and I've always had it enabled. Currently, the markers are set to last 31 days. So, if you scroll a few pages back in any forum, threads from Aug 6th and older will all look like you've read them even if you haven't.
