Again today, after dist-upgrade. But this time gdm was not upgraded, although xorg-driver-fglrx (which has atieventsd) was.
I tried to look deeper into this, and it seems that in this case it is caused by atieventsd calling "xauth add/remove -f /home/xxx/.Xauthority" as root, which triggers the ownership change. Do you have this installed (xorg-driver-fglrx)?
In any case, to debug I made a simple shell wrapper for xauth which logs when it is called and who calls it. Let me know if you need this.
Again today, after dist-upgrade. But this time gdm was not upgraded, although xorg-driver-fglrx (which has atieventsd) was.
I tried to look deeper into this, and it seems that in this case it is caused by atieventsd calling "xauth add/remove -f /home/xxx/ .Xauthority" as root, which triggers the ownership change. Do you have this installed (xorg-driver- fglrx)?
In any case, to debug I made a simple shell wrapper for xauth which logs when it is called and who calls it. Let me know if you need this.