brian-ithil: Thanks for testing! The primary package that needs to be updated is `libmutter-14-0`; you can do that easily with `apt install -t noble-proposed libmutter-14-0`, and it will automatically resolve other dependencies from -proposed.
Log-out and restart gdm3 is indeed sufficient to pick up the update. But note that the livecd for noble still defaults to X.org while the fix only affects Wayland so we need to test Wayland. To do so in a livecd, edit `/etc/gdm3/custom.conf` to remove the `WaylandEnable=false` line, then restart gdm3. Once logged-in, verify that it is a Wayland session with `echo $XDG_SESSION_TYPE`. Then you can try to reproduce and check if the update fixes the issue. ** Description changed: [ Impact ] On some machines when the screen blanks, the LCD backlight stays on. This was traced to two issues in mutter: https://gitlab.freedesktop.org/drm/amd/-/issues/662#note_2731990 > I recently discovered that mutter was disabling DPMS off again on receiving a hotplug event from udev. I don't know any reason for that, removing it allows my monitor to go to sleep eventually. Note that when mutter runs on Xorg, it doesn't explicitly disable DPMS off but just queries the current DPMS state from Xorg. Since the issues are reproducible with Xorg and other Wayland DEs, maybe Xorg drivers and other Wayland compositors do something like what mutter did as well. > On receiving a hotplug event from udev, mutter now waits until no further hotplug events have arrived for at least one second, only then does it query the current KMS state. This avoids issues due to monitors generating hotplug events and temporarily appearing disconnected. It might be nice if something like this was done in the kernel if possible, not sending any hotplug event to user space if EDID hasn't changed, or something along those lines. + + The fix proposed in this mutter update only affects Wayland. [ Workarounds (reported to work by some people) ] * Configure the monitor (in its own menus) to not auto-switch inputs. * Change from HDMI to DisplayPort cables. * Disable HDMI audio output. [ Test Plan ] 0. Make sure you're using an LCD (not OLED) so you can see if the backlight is on. 1. Log-in to an Ubuntu Wayland desktop session 2. In Settings -> Power -> Screen Blank, set the inactivity period to 1 minute. 3. Verify after 1 minute that the screen is blank and the backlight is also visibly off. 4. Verify that the screen is turned back on after interacting with the system. [ Regression Test Plan ] 1. Plug in a monitor: - -> Verify that the desktop extends to the new monitor + -> Verify that the desktop extends to the new monitor 2. Unplug a monitor: - -> Verify that mutter does not crash and log you out + -> Verify that mutter does not crash and log you out [ Where problems could occur ] Mutter is the GNOME component driving the display. The patches modify how mutter reacts to monitor hotplug events and when it should turn the monitor back ON. Problems would manifest when plugging in/out monitors. The "Regression Test Plan" tries to verify that no regressions are introduced. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1971434 Title: Display powersave only blanks, but does not turn off To manage notifications about this bug go to: https://bugs.launchpad.net/gnome-settings-daemon/+bug/1971434/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
