Recently, after an update, I experienced some rather irritating problems with GNOME or any other GTK+-based environment (Xfce, GDM). Xinerama was not working properly. That is, I have TwinView enabled, but everything would span both monitors (except for maximized applications). This includes the GNOME panel, GDM login screen, etc. Xfce would recognize only one monitor rather than two. I spent many hours trying to figure out the problem. I initially thought it might bt GTK+, since that was updated before the problem, so I upgraded it even further. That was a mistake. The solution was to downgrade it.

The problem was that I was using the GNOME overlay in layman in order to keep up to date with GNOME (and I believe grab 2.22 before it was unmasked or available in portage). Unfortunatly, it kept going. It upgraded to 2.23, which is an unstable development version of GNOME. It has a number of problems, not just that. For example, the splash screen would not disappear unless you threatened to blow its brains out with the kill applet or xkill. Removing the overlay and “upgrading” (downgrade to 2.22) fixed all the problems.

So, moral of the story, don’t use the GNOME overlay for a home desktop or any sort of production environment. It’s great to keep up to date…but it’s better when the stuff actually works.