Not sure if this belongs here or upstream, let me know if I need to report somewhere else. Operating System: Ubuntu 22.04 KDE Plasma Version: 5.24.4 KDE Frameworks Version: 5.92.0 Qt Version: 5.15.3 Kernel Version: 5.15.0-33-generic (64-bit) Graphics Platform: X11 Processors: 12 × AMD Ryzen 5 5600X 6-Core Processor Memory: 15,5 GiB of RAM Graphics Processor: NVIDIA GeForce RTX 3060 Ti/PCIe/SSE2 2 monitors setup : left monitor uses direct play cable / right monitor uses hdmi cable / primary is the left monitor 1/ start PC with only left monitor switched on, right monitor is off unlock keyring window is invisible because it is displayed on the right monitor 2/ when you launch some applications you see nothing because they are being sent to the second monitor eventhough it is turned off
Many monitors don't register themselves as "off" when you turn off the power button, and only tell that to the system when you actually physically unplug them. For these monitors, the "off" button is basically a "set me to zero brightness" button, which is not particularly helpful, but that's a hardware problem. I have one such monitor so I feel your pain. Does everything work better if you physically unplug the cable for that monitor?
Interesting comment, thanks. I put one window on my second (right/HDMI) monitor and tested the following: 1- switching off the monitor with the on off button (the one on front of the monitor) : changes nothing (the window stays on the right monitor) 2- switching off the monitor with the power off button (the one behind the monitor that shuts down AC) : changes nothing 3- removing the HDMI cable from the graphic card : now linux understands that it has only one screen and moves the open windows to the single monitor 4- removing the HDMI cable from the monitor : also works So it means that something has changed because with the same monitors tests 1- and 2- used to work with my previous PC which was in 20.04 Gnome version. There were many other multi-monitor bugs also but not this one.
Second test: I put one window on my first (left/DirectPlay) monitor and tested the following: 1- switching off the monitor with the on off button (the one on front of the monitor) : changes nothing (the window stays on the left monitor) 2- switching off the monitor with the power off button (the one behind the monitor that shuts down AC) : WORKS !!! 3- removing the DP cable from the graphic card : now linux understands that it has only one screen and moves the open windows to the single monitor So, there is a difference between HDMI and DP behavior.
Ok, so maybe 1 and 2 are things we need to fix in KWin.
This happens here too. Three monitors, 2x DisplayPort and 1x HDMI. Often the desktop runs in the background and I turn off 1x DP and 1x HDMI display. This is done via a smart switch physically cutting the power to the monitors. The 1x DP monitor disappears, the 1x HDMI still shows up in Display Configuration as connected as long as the HDMI cable is present. Operating System: EndeavourOS KDE Plasma Version: 5.24.90 KDE Frameworks Version: 5.94.0 Qt Version: 5.15.4 Kernel Version: 5.18.1-zen1-1-zen (64-bit) Graphics Platform: Wayland Processors: 12 × 11th Gen Intel® Core™ i5-11400 @ 2.60GHz Memory: 31,1 GiB of RAM Graphics Processor: AMD Radeon RX 5500 XT Manufacturer: Gigabyte Technology Co., Ltd. Product Name: B560M AORUS PRO AX
Ok, you got me motivated to do more testing :) For test 3, I exchanged the cables between my 2 monitors so now my left monitor is primary and HDMI (was primary and DP) and my right monitor is DP (was not primary and HDMI). I put one window on my second (right/DP) monitor and tested the following: 1- switching off the monitor with the on off button (the one on front of the monitor) : WORKS ! (the window moves to the left monitor) 2- switching off the monitor with the power off button (the one behind the monitor that shuts down AC) : Works 3- removing the DP cable : Works So it seems that it is not only a story of HDMI/DP, it also depends if the monitor is primary or not.
The primary monitor setting has no relevance for anything except where the panels are. The monitor not reporting that it's off to the computer is something that's a hardware problem, we can't do anything about that. The monitor not being detected as unplugged when HDMI is used and its power is cut might also be a hardware problem, if part of the monitors logic is powered by the HDMI cable. It might also be a driver bug though, so reporting this to your graphics vendors could be useful. In both cases though, there's sadly nothing we can do about this.