I was looking at my PMs and I noticed that quite a few of them only had my username as a participant, even if the person I PMed responded to me. What's stranger is there are also ones where the person is shown as a participant but others not. It's not the biggest of bugs to be sure, but for like PMs I sent to someone and they never responded back, since the participant doesn't show up how am I even suppose to know if it got sent to them? Anyway this is very strange and should be looked into.

@IceHeart That means that they deleted the PM.

@IceHeart Yeah, it is a new feature since we can delete pm's. If their name isn't there anymore it means they deleted it. Whatever you send from that point on will not be delivered to them because it is no longer in their pm box. It's not a glitch. You would have to start a new pm if you want a response. (You still have it because you haven't deleted it obviously but yeah, they won't get it because they don't have it.)

View it as "I am still subscribed to this thread", but the others have hit the mark pretty well.

@IceHeart Others have answered, but I do need to clarify the UI to indicate who the participants were and that they left the conversation.