I often have 3-4 PM windows open at a time. Since the people in them aren't always talking, I roll them up and stick them below the minimap, so I can see better. However, this becomes a problem if the top person, for example, talks, then the 2nd person does. It's easy, when the PM windows are rolled up except for one, to forget that someone whose window was covered by the unrolled window said something, especially if there's a lot going on on screen. I know that if someone whose window is hidden talks, the title bar pops above the window hiding it and flashes red. But that doesn't help if they only say one thing, whether I'm in the middle of talking to the unrolled person, or if I just unroll someone's window to cover theirs after they speak.
So my suggestion (finally) is to have PM windows "stick" to each other, top to bottom, if you move them close enough together. So if Dubstep PMs me, then I PM Aniya, I can drag Aniya's window to the bottom of Dubstep's, and then roll up Dubstep's. Aniya's will automatically follow (not roll up, just move up). If I unroll Dubstep's, Aniya's will move down. Perhaps I can even move Dubstep's window around and Aniya's will follow. Of course, I can still close or roll up Aniya's or drag it off Dubstep's if I want.
This would hopefully work for any number of people I have PM windows open for, as long as there's room on the screen, of course. I don't know what would happen or what could be done if I unroll a window, causing one stuck to it to be shoved off the bottom of the screen.
So my suggestion (finally) is to have PM windows "stick" to each other, top to bottom, if you move them close enough together. So if Dubstep PMs me, then I PM Aniya, I can drag Aniya's window to the bottom of Dubstep's, and then roll up Dubstep's. Aniya's will automatically follow (not roll up, just move up). If I unroll Dubstep's, Aniya's will move down. Perhaps I can even move Dubstep's window around and Aniya's will follow. Of course, I can still close or roll up Aniya's or drag it off Dubstep's if I want.
This would hopefully work for any number of people I have PM windows open for, as long as there's room on the screen, of course. I don't know what would happen or what could be done if I unroll a window, causing one stuck to it to be shoved off the bottom of the screen.