Fluxbox currently requires a specific configuration directive to enable xinerama (X extension to stretch a single window manager across multiple screens) support. It's currently necessary to to edit the ebuild file to enable support for xinerama (--enable-xinerama). I'd imagine that there are other programs out there, especially window managers with similar requirements. It would be nice to see a new USE variable to allow the ebuild packagers to automatically configure support for such. I think the best choice would probably be 'multimon' though 'xinerama' should be just as clear to people who've had to configure it.
Created attachment 1950 [details] Sample of how I'd like to see the fluxbox ebuild work with a new use variable.
-r4 of fluxbox will have xinerama always enabled... we don't want to require users to recompile everything when they get a 2nd monitor, and I don't see a reason to leave this capability out by default.