Comment 30 for bug 1308105

In xfsettingsd 4.11.2 there appears to be a regression that when a TV hooked up to the computer via HDMI gets power cycled, it stops displaying anything.

It happens via a RANDR event being sent to all X clients when the TV gets turned off.

xfsettingsd thinks that it should switch to an internal output, but desktops don't have one. So when the TV comes back on the bus it seems like it's an extra monitor and xfsettingsd gets confused.

xfce4-settings(displays): RRScreenChangeNotify event received.
xfce4-settings(displays): Refreshing RandR cache.
xfce4-settings(displays): Detected CRTC 447.
xfce4-settings(displays): Detected CRTC 448.
xfce4-settings(displays): Noutput: before = 1, after = 0.
xfce4-settings(displays): Output disconnected: HDMI-0
xfce4-settings(displays): Disabling CRTC 447.
xfce4-settings(displays): No active output anymore! Attempting to re-enable the internal output.
xfce4-settings(displays): RRScreenChangeNotify event received.
xfce4-settings(displays): Refreshing RandR cache.
xfce4-settings(displays): Detected CRTC 447.
xfce4-settings(displays): Detected CRTC 448.
xfce4-settings(displays): Noutput: before = 0, after = 0.
xfce4-settings(displays): RRScreenChangeNotify event received.
xfce4-settings(displays): Refreshing RandR cache.
xfce4-settings(displays): Detected CRTC 447.
xfce4-settings(displays): Detected CRTC 448.
xfce4-settings(displays): Detected output 452 HDMI-0.
xfce4-settings(displays): Noutput: before = 0, after = 1.
xfce4-settings(displays): New output connected: HDMI-0

Additional details can be found on the Ubuntu bug report located here:
https://bugs.launchpad.net/ubuntu/+source/xfce4-settings/+bug/1308105