Created attachment 182091 [details] `plasmashell --replace 2>&1 | tee plasmashell.log` output SUMMARY I use a StarTech SV431HDU3A2 4-port KVM Switch to switch between PCs and servers in my homelab. When switching to another input on Kubuntu 25.04 Plucky, plasmashell goes black (taskbar vanishes, windows are unaffected) and must be restarted with either `pkill -9 plasmashell` or `plasmashell --replace`. This only occurs under X11, and due to some test automation software I use being broken under Wayland due to Wayland security design, I can only use X11. Also tested with latest KDE backports for Kubuntu Plucky. (plasmashell 6.3.5, tested June 8 2025 at 2:59AM PST) STEPS TO REPRODUCE 1. Log in with user account under X11. 2. Switch to another KVM input. 3. Switch back to original input. OBSERVED RESULT Area where taskbar and taskbar widgets used to exist is entirely black. Taskbar eventually disappears entirely and maximized windows shift to fill space. EXPECTED RESULT Taskbar and all taskbar widgets display normally. SOFTWARE/OS VERSIONS Linux/KDE Plasma: ??? KDE Plasma Version: 6.3.4 KDE Frameworks Version: 6.12.0 Qt Version: 6.8.3 ADDITIONAL INFORMATION * I have deliberately disabled audio-related kernel modules on the machine in question, thus the warning related to `auto_null.monitor` is expected behaviour.
Created attachment 182092 [details] Full-screen view of behaviour with kinfo displayed.
Created attachment 182850 [details] Additional information (kscreen.xcb.helper and kscreen.xrandr journald logs) Noticed this additional information when looking at KSystemLog entries between KVM switchings. Hope this helps.