SUMMARY I set my power management to have my screen dim after 5 min, then turn off the screen after 10 min of no activity. This worked on the previous version of KDE plasma on Fedora 42. As soon as I updated to the new version, the second monitor will consistently turn off with the main monitor and then turn back on. It does this after a fresh boot and with other programs on, and doesn't matter if I have a program on the screen or not. And it is consistently always the second monitor, my main monitor works just fine as far as I have observed this issue as well as before the issue occurred. STEPS TO REPRODUCE 1. set dim screen to (x) time and set turn screen off (x) time. 2. Fedora 42 on KDE Plasma 6.4.0 3. OBSERVED RESULT 2nd screen turns off then on Main screen turns off and stays off until an input is registered EXPECTED RESULT both screens stay off until an input is registered SOFTWARE/OS VERSIONS Operating System: Fedora Linux 42 KDE Plasma Version: 6.4.0 KDE Frameworks Version: 6.15.0 Qt Version: 6.9.1 Kernel Version: 6.14.11-300.fc42.x86_64 (64-bit) Graphics Platform: Wayland Processors: 24 × AMD Ryzen 9 5900X 12-Core Processor Memory: 64 GiB of RAM (62.7 GiB usable) Graphics Processor: AMD Radeon RX 6900 XT ADDITIONAL INFORMATION main screen is 1440p, 144hz , HDR on and the second screen is 1080p 75hz no HDR
I'm not seeing this on git-master Screens Laptop 3840 x 2400 @ 150% 2 external monitors 3440 x 1440 @100 % - connected via USB-C dock
A possibly relevant merge request was started @ https://invent.kde.org/plasma/kwin/-/merge_requests/7868
Git commit e177e1d2da8a278f85d5d3e24ffdc01e7c2eaca6 by Xaver Hugl. Committed on 04/07/2025 at 13:10. Pushed by zamundaaa into branch 'master'. backends/drm: don't use UUID to identify outputs The UUID is only set later by the output configuration system, so it can't be used in the drm backend when deciding the dpms state of a "new" output. This changes it to use EDID ID, EDID hash or connector name instead, which are valid much earlier and are reliable enough for the dpms workaround. Related: bug 493879, bug 505953 M +19 -3 src/backends/drm/drm_backend.cpp https://invent.kde.org/plasma/kwin/-/commit/e177e1d2da8a278f85d5d3e24ffdc01e7c2eaca6
Git commit 8f331a268cf1e457b8727080763869e1b426dae8 by Xaver Hugl, on behalf of Xaver Hugl. Committed on 04/07/2025 at 13:57. Pushed by zamundaaa into branch 'Plasma/6.4'. backends/drm: don't use UUID to identify outputs The UUID is only set later by the output configuration system, so it can't be used in the drm backend when deciding the dpms state of a "new" output. This changes it to use EDID ID, EDID hash or connector name instead, which are valid much earlier and are reliable enough for the dpms workaround. Related: bug 493879, bug 505953 (cherry picked from commit e177e1d2da8a278f85d5d3e24ffdc01e7c2eaca6) Co-authored-by: Xaver Hugl <xaver.hugl@kde.org> M +19 -3 src/backends/drm/drm_backend.cpp https://invent.kde.org/plasma/kwin/-/commit/8f331a268cf1e457b8727080763869e1b426dae8