SUMMARY After I login to a wayland plasma session with sddm the desktop will appear temporarily, then after a few seconds the screen will go completely black (no cursor or anything else) and remain black. STEPS TO REPRODUCE 1. Select Plasma Wayland Session from SDDM 2. Enter log in password and hit enter OBSERVED RESULT Plasma desktop appears briefly (several seconds) and then the screen goes completely black and stays black. EXPECTED RESULT Plasma desktop appears and remains visible. SOFTWARE/OS VERSIONS Linux/KDE Plasma: openSUSE Tumbleweed 20241025 KDE Plasma Version: 6.2.2 KDE Frameworks Version: 6.7.0 Qt Version: 6.8.0 ADDITIONAL INFORMATION The monitor appears to still receive signal. Additionally, I can switch to a TTY and then back to the plasma session and then the desktop will sometimes reappear and then stay visible. If I kill the session with ctrl+alt+backspace x2 I can switch to an X11 plasma session which works fine. This occurs after every wayland plasma login with OpenSuse Tumbleweed and persists even after a full reinstall of the OS. (It occurs on Fedora KDE (wayland) also). Other DE’s do not cause the issue to arise (I have installed alternative DEs to check whether it was an OpenSuse and/or Fedora issue - for instance Cinnamon Wayland on Fedora works fine). I have already posted this issue in KDE discussion forum however no one has been able to assist in resolving the issue. I have never filed a bug report before and am unsure which logs/additional information I should provide with this report nor how to do the debugging process (despite reading the articles on this).
Do you have extra empty entries in the "Device:" dropdown menu in System Settings > Display & monitor? If so, I think this is very likely Bug 493810.
(In reply to Nate Graham from comment #1) > Do you have extra empty entries in the "Device:" dropdown menu in System > Settings > Display & monitor? If so, I think this is very likely Bug 493810. No, only one device appears on that page. I was able to quickly take a screenshot of this before the screen went black and can upload it if it would be useful.
Sure, that might be useful!
Created attachment 175319 [details] Screenshot showing one device under display & monitor
Created attachment 175320 [details] Bootlog from today Bootlog from today; logging in to plasma wayland session (with black screen bug occurring), then into X11 session.
(In reply to Nate Graham from comment #3) > Sure, that might be useful! I have uploaded the screenshot as well as a bootlog from journalctl in case it can help.
I have resolved this issue. It appears to be an issue with powerdevil DDC/CI and my monitor. Disabling DDC/CI in the powerdevil service has fixed it.
Thanks for the info; that's a useful workaround to know. which shows us it's a Powerdevil issue. Moving over there.
*** This bug has been marked as a duplicate of bug 494899 ***