PM list is formatted like an expanded group of nested comments
I can't really show you a screenshot without putting the first line of dozens of PMs into a thread, but it looks like this:
PM1 - yes hello this is a line in a PM it goes on for the complete first line of the PM
___PM2 - doot doot this is the second PM and goes on for the complete first line of the PM too
______PM3 - greetings we regret to inform you that your social security number has been scrambled
and on and on in a tree like that until it's smashed against the righthand edge, then it begins again.