If you start manually from the console it works, from x11-login.service it won't
Debian Stretch used non-root Xorg by default. This might cause it. To revert to the old root behaviour install xserver-xorg-legacy
However the problem remains. Pin pointed the error to:
[ 19.214] (II) systemd-logind: took control of session /org/freedesktop/login1/session/_31
[ 19.214] (II) xfree86: Adding drm device (/dev/dri/card0)
[ 19.215] (II) systemd-logind: got fd for /dev/dri/card0 226:0 fd 8 paused 1
[ 19.215] (EE) Error systemd-logind returned paused fd for drm node
[ 19.215] (II) systemd-logind: releasing fd for 226:0
Which doesn't show up in an interactive start. The problem is caused through systemd... :(
If you start manually from the console it works, from x11-login.service it won't
Debian Stretch used non-root Xorg by default. This might cause it. To revert to the old root behaviour install xserver-xorg-legacy
However the problem remains. Pin pointed the error to:
Which doesn't show up in an interactive start. The problem is caused through systemd... :(