I guess it's the mesa transition still going on. It seems it has problems with Nividia. As PackRat pointed out it can make the whole Xsrever go away.
I also read somewhere early this summer that a big Xorg upgrade was coming. No idea if this is part of it or just the beginning. Haven't found any further reference yet. At least python has settle down.
This is an interesting one because Debian announced that Wayland will replace Xorg x11 in Debian 10 that is due in 2019
Is it possible Sid could have that replacement this early?
So much continues to change with Debian... Makes me wonder how much longer VSIDO will be Sid or even around
That's really sad. I wouldn't like to see Vsido vanishing.
I'm not happy with the Wayland switch either, that means that daily drivers in my workflow like fluxbox, urxvt, dmenu, rofi, xcalc and all the Xresources, xdotool, xbindkeys, xset, etc... tweaks and tricks will render useless. I'm not against evolution and changes, but the alternatives I'm seeing are not appealing at all at least for now. Also I'm pretty sure that the transition wayland+X support won't be short or smooth.