https://bugs.kde.org/show_bug.cgi?id=513100
--- Comment #10 from NitramO <[email protected]> --- (In reply to NitramO from comment #9) > (In reply to NitramO from comment #8) > > (In reply to Oliver Beard from comment #7) > > > Journal logs may be more revealing — with a driver issue, I expect to see > > > the Nvidia driver practically screaming. > > > > > > Could you take a note of the time before logging in, then log in, attempt > > > to > > > show a Task Manager thumbnail, and then note the time and log out? > > > > > > With these times, you can extract the logs with the command: > > > > > > journalctl --since "14:00:00" --until "16:00:00" > logs.txt > > > > > > which will create a file 'logs.txt' in your current directory and attach > > > them to this bug report? You could do this from a TTY after the session, > > > or > > > during if it is not too unstable. > > > > I will try that and come back here to give you the results. > > > > Other than that, is there anything I can do to try to fix it? Like > > reinstalling a package or something, because it may be corrupted since I had > > a lot of trouble installing the last update and I had to reinstall some > > other packages after it (for example, some of my applets were still there > > but not recognized, so I had to install the packages again for them to work > > again). > > Part 1: https://pastebin.com/raw/2rZKvkf6 > > Part 2: https://pastebin.com/raw/C8X9na5j > > Good luck... 🙃 UPDATE: Root Cause Identified and Fixed! After extensive debugging, I found the root cause of this issue. CAUSE: The environment variable __NV_PRIME_RENDER_OFFLOAD=1 was set globally via: ~/.config/environment.d/90-nvidia.conf This file contained a single line: __NV_PRIME_RENDER_OFFLOAD=1 This variable forces all applications to render on the NVIDIA dGPU. On hybrid GPU laptops running Wayland, this breaks buffer sharing between the iGPU (used by KWin compositor for display) and the dGPU (forced for all app rendering). The Task Manager thumbnails fail to capture window content properly, resulting in black previews. The Overview effect (Meta+W) still works because it uses a different capture method. HOW THIS FILE APPEARED: When I reported this bug, I mentioned that it appeared after a KDE update. However, around the same time, I also updated my NVIDIA drivers from version 570 to the latest 580-open (which was marked as recommended). The 90-nvidia.conf file was most likely auto-generated during this NVIDIA driver update, not by the KDE update itself. This explains why I initially associated the bug with the KDE update, as both updates happened simultaneously. I was not aware of this file's existence until investigating this bug. SOLUTION: 1. Remove or rename the file: mv ~/.config/environment.d/90-nvidia.conf ~/.config/environment.d/90-nvidia.conf.bak 2. Clear GPU caches: rm -rf ~/.nv rm -rf ~/.cache/nvidia rm -rf ~/.cache/mesa_shader_cache rm -rf ~/.cache/mesa_shader_cache_db rm -rf ~/.cache/qtshadercache* 3. Log out and log back in (or reboot) RESULT: After applying this fix, window thumbnails in the Task Manager are now displaying correctly. Updated system info: - Operating System: KDE neon User Edition - KDE Plasma Version: 6.5.4 - KDE Frameworks Version: 6.21.0 - Qt Version: 6.10.1 - Kernel Version: 6.14.0-37-generic (64-bit) - Graphics Platform: Wayland - Graphics Processor 1: NVIDIA GeForce RTX 4060 Laptop GPU (driver 580-open) - Graphics Processor 2: Intel Iris Xe Graphics - Memory: 32 GB RAM -- You are receiving this mail because: You are watching all bug changes.
