As of now, the message notification/party invite is not reliable, because any area change basically means you dont get notified of a message. This means you might think a friend didnt want to reply to your message when in reality they never even realized you messaged them!.
This usually means that the easiest way to contact a friend is to party invite them multiple times in hopes of them joining your party so you can voice talk to them.
A potentially simple fix is to change the color of the message UI icon to notify unread messages., shown in this super cool mockup i i did.
The reason this would be helpful is, we players open this menu very frequently, and we dont open the messages that often.
I would add as well a ‘mark all as read’ so you can bulk mark them all.