SUMMARY When I connect my monitor, it usually shows up with 100% brightness instead of what it was set to when I last connected it. Sometimes, it shows up with a very dim, but not off setting (maybe 0%). The monitor also has speakers in it, and the volume is always set to 100% when it connects as well, which can be quite terrifying. I have no idea how to link this bug to both KScreen and whatever handles the volume. FWIW, it will also sometimes do that when reviving from sleep while connected. Sometimes, it just won't show the brightness control for external monitor after sleeping. When it gets into that state, I can't even unplug and replug the monitor to get the settings back. It usually will come back if I logout and log back in without a reboot. STEPS TO REPRODUCE 1. Turn on computer with monitor connected. 2. Login. 3. Be sad now that I need to reset my brightness/volume settings. or 1. Setup my volume/brightness settings 2. Let computer go to sleep 3. Wake it up 4. Either re-setup my volume/brightness settings...or be sad because the brightness for the connected monitor no longer shows up. OBSERVED RESULT I'm sad because I have to reset my volume/brightness all the time. I'm always being jump scared by my 100% volume. EXPECTED RESULT My volume/brightness settings are remembered and applied. I never have to think about it. SOFTWARE/OS VERSIONS Linux/KDE Plasma: Fedora Rawhide, kernel version 6.13.0-0.rc7.20250114gitc45323b7560e.56.fc42.x86_64 KDE Plasma Version: 6.3 Beta (6.2.90) KDE Frameworks Version: 6.10.0 Qt Version: 6.8.1 ADDITIONAL INFORMATION My external monitor is a 43" Dell U4320Q/3HTJW13. It seems to works really well otherwise.
> it usually shows up with 100% brightness instead of what it was set to when I last connected it This is Bug 494408, which is fixed in Plasma 6.3. > The monitor also has speakers in it, and the volume is always set to 100% when it connects as well, > which can be quite terrifying This is unfortunately an upstream PipeWire bug: https://gitlab.freedesktop.org/pipewire/wireplumber/-/issues/744. Feel free to leave a comment there. > Sometimes, it just won't show the brightness control for external monitor after sleeping This is Bug 482713, which isn't fixed yet. Marking as a duplicate of that one. In the future, please open multiple bug reports to report multiple issues. Thanks! *** This bug has been marked as a duplicate of bug 482713 ***
(In reply to Wren Turkal from comment #0) > 3. Be sad now that I need to reset my brightness/volume settings. When you reset your brightness/volume settings, do you use Plasma's brightness slider, accessible in the Brightness and Color applet and in the Display Configuration settings page? Or do you use your monitor's OSD menu? For Plasma 6.3, KWin will not remember external monitor brightness changes. I'm assuming you've set the value in Plasma as you mention the brightness control no longer showing up sometimes. But please confirm. Enabling verbose logging for the plasma-powerdevil service could provide insight as to what's happening: https://invent.kde.org/plasma/powerdevil/-/blob/master/README.md#troubleshooting--reporting-bugs (note that this doesn't include KWin verbose logging, so we may still miss some context)
I only use the Plasma brightness slider (either from the systray or in the display settings).
I think you are saying that Plasma doesn't remember brightness ever for a plugged in monitor. Is that correct? That seems kinda awful. Is that intentional or is this some kind of bug? Kinda weird that it remembers my screen layout and settings other than brightness. Just to give you a little more about my use case. I plug in this monitor whenever I am in my office. This isn't a once every so often monitor. I use it most days and must reset the brightness (if the slider doesn't disappear) pretty much every time I resume from sleep or boot the machine with the monitor connected.
(In reply to Wren Turkal from comment #4) > I think you are saying that Plasma doesn't remember brightness ever for a > plugged in monitor. Is that correct? Sorry, I phrased this poorly. Plasma will of course remember brightness for an external monitor. What it will not do (for the time being) is realize when the monitor itself has initiated the brightness change through its own hardware buttons. We can read the monitor's brightness values but we won't get notified when a change happens, so for now we left "read brightness again" heuristics for a later time. As of Plasma 6.3, we only read brightness when the monitor is first detected to initialize settings for a monitor that KWin has not seen before. > Just to give you a little more about my use case. I plug in this monitor > whenever I am in my office. This isn't a once every so often monitor. I use > it most days and must reset the brightness (if the slider doesn't disappear) > pretty much every time I resume from sleep or boot the machine with the > monitor connected. Thanks. What I'm reading is that you're indeed using Plasma's brightness slider to re-adjust the brightness, you're not using your monitor's hardware buttons to do this. By using Plasma's brightness slider, the brightness would get stored and should indeed be restored next time your monitor gets connected again. The fact that this does not happen (reliably, at least) is indeed a bug. If you can collect some logs as described earlier, we may find an indication of what's going wrong.