Hi, when suspending while xfsettingsd is running, at resume the screen is black (like, backlight at 0) and it's not possible to set the brightness up. Switching to console and raising the brightness works there, but as soon as I switch back to X, the backlight is at 0 (completely off). A bit strangely, it does happen when I close the lid (so suspend is triggered by xfce4-power-manager, then upower, then pm-utils) but not when I use the Fn+F4 shortcut (which I think is handled directly in-kernel through thinkpad-acpi). In any case, it's a regression which appearead in 4.11.
Actually it might not be only backlight related. When trying to play with xrandr and xfsettingsd, I have errors about “failed to set crtc”.
I can't seem to reproduce this anymore, marking as invalid, will reopen if it reappears.