Anomaly or Glitch? Threads not shaded today

When I checked in this a.m. I wasn't logged on. I rarely log off. OK, no biggie. I logged in.

When I checked Home Page, a new thread reply was indicated. Clicked on and the reply was 2-3 days old. (don't remember now)

Every forum I looked at was showing the basic gray/white for every thread. None indicated I'd been reading it, new posts, etc. As new posts were u/l'd they were "lighting" up.

I've been gone for a few hours now. Some of the threads are indicating "read, new, etc." correctly. But some of the forums are back to the basic gray/white.

Is this just me?

ty