Selfy, I think I finally have it.

I was searching through my inbox to find a particular PM, and when I would click on a PM, the member's name, or whatever in the list then go back to it...what I'd already viewed in this particular online session was green as opposed to blue.

I think that's what you're referring to. The one's that are green is where you've clicked on the name, subject, etc. I'm almost positive they all default back to blue with the next session.

KD