The current screen 4.4.0 ebuild forces the socked dir to "/tmp/screen":
The default behavior of screen is to use $HOME/.screen/. This has the advantage that this works flawlessly with screen installed without suid. There seems to be no way to restore the default behavior when a hardcoded dir is set compile-time.
I'd propose to just remove the --with-socket-dir parameter from the configure line and use the default upstream behavior. If there's a strong need for some for the hardcoded behavior we could also make this configurable via a use flag.
Can I raise attention to this issue?
I'm maintaining a copy of the screen ebuild for my own use cases due to this issue, but that shouldn't be. I really don't see why we're hardcoding something to a non-default where upstream's default should work perfectly well.