SUMMARY Since Plasma 5.27.8 task manager occasionally stops tracking open windows on a wayland session. This issue looks deceptively similar to Bug 429168 however it only appeared between 5.27.7 and 5.27.8. Although they manifest in the same manner they are probably caused by different issues. I also get the same warning as in Bug 429168 when starting up plasmashell from the terminal ("org.kde.kf5.kwindowsystem.kwayland: This compositor does not support the Plasma Window Management interface") and also as in Bug 429168 the issue appears on all flavours of task manager. Reverting plasma-workspace (which provides plasmashell) back to 5.27.7 stops the problem from appearing. I browsed the git commits of plasma-workspace between 5.27.7 and 5.27.8 and there were a few commits that *look* like they might be associated with this, for instance this [0] or this [1] but unfortunately I am not qualified enough to say. [0] https://invent.kde.org/plasma/plasma-workspace/-/commit/b235a5900107ef1cec7d6ac30f5569ee5e3357c1 [1] https://invent.kde.org/plasma/plasma-workspace/-/commit/cb7dfe90f2a91f20c40a7e4744112602534aee38 STEPS TO REPRODUCE 1. Open a graphical application OBSERVED RESULT Task manager does not update EXPECTED RESULT A new icon appears on the task manager to track the status of the new window SOFTWARE/OS VERSIONS Linux/KDE Plasma: Archlinux (available in About System) KDE Plasma Version: 5.27.8 KDE Frameworks Version: 5.110.0 Qt Version: 5.15.11 ADDITIONAL INFORMATION With proprietary NVIDIA driver. Problem appears only on Wayland Sessions.
The two commits are not in 5.27. They are only for 6.0. Did you also see the panel frozen when you see the bug?
Yes, this usually happens after a freeze of the panel which is, from what I understand, a common issue with pre-6.0 and nvidia. However, restarting plasmashell doesn't fix the problem, the taskbar becomes responsive again but no windows are tracked, only pinned applications and applets are shown. Even restarting the session (or the computer) doesn't fix the issue. I tested with a new user, changed nothing in the configuration and waited until the panel froze again and indeed the same thing happened. Then I nuked the new user's .config and .local to force a fresh plasma session. The panel then works again until it freezes, rinse, repeat. The only difference between 5.27.7 and 5.27.8 is that with 5.27.7 a "killall plasmashell && kstart5 plasmashell" or "plasmashell --replace" addresses the issue whereas with 5.27.8 even restarting the shell does not.
Just to add one more piece of information: the difference between a "regular" freeze and the issue I'm describing is the presence of the "org.kde.kf5.kwindowsystem.kwayland: This compositor does not support the Plasma Window Management interface" in the logs when starting plasmashell.
Issue persists on 5.27.9
I have the same problem in Fedora 39, recently upgraded from Fedora 38: Operating System: Fedora Linux 39 KDE Plasma Version: 5.27.9 KDE Frameworks Version: 5.111.0 Qt Version: 5.15.11 Kernel Version: 6.5.11-300.fc39.x86_64 (64-bit) Graphics Platform: Wayland Symptoms: - Icons in the taskbar remain after the window has been closed. They are not responsive, right-clicking shows the taskbar menu - No new icons beyond the third - Icons for the windows not closed work (i.e., they minimize/restore the window) - The network icon shows the VPN lock even when the VPN has been disconnected (it is reset upon logout-login) - Digital clock has frozen (but "copy to clipboard" shows the correct time) So taskbar is not completely frozen in my system
In addition, the taskbar shows the wrong icon. I closed a chrome browser but the icon remained in the taskbar. On clicking, it restores/minimizes a different window.
(In reply to emelenas from comment #5) > I have the same problem in Fedora 39, recently upgraded from Fedora 38: > Operating System: Fedora Linux 39 > KDE Plasma Version: 5.27.9 > KDE Frameworks Version: 5.111.0 > Qt Version: 5.15.11 > Kernel Version: 6.5.11-300.fc39.x86_64 (64-bit) > Graphics Platform: Wayland > > Symptoms: > - Icons in the taskbar remain after the window has been closed. They are not > responsive, right-clicking shows the taskbar menu > - No new icons beyond the third > - Icons for the windows not closed work (i.e., they minimize/restore the > window) > - The network icon shows the VPN lock even when the VPN has been > disconnected (it is reset upon logout-login) > - Digital clock has frozen (but "copy to clipboard" shows the correct time) > > So taskbar is not completely frozen in my system I can confirm this on Fedora 39 Spin and openSUSE tumbleweed. The Task Manager mouse hover + live thumbnail seems to cause problems While xorg live thumbnail showing only video but Wayland showing entire browser or video player. and doing this it sometimes stops responding. KDE Plasma Version: 5.27.10 KDE Frameworks Version: 5.112.0 Qt Version: 5.15.11 Kernel Version: 6.6.6-1-default (64-bit) Graphics Platform: Wayland Graphics Processor: NVIDIA GeForce RTX 2080/PCIe/SSE2
Issue keeps happening in Plasma 6, although there is no panel freeze anymore. The "This compositor does not support the Plasma Window Management interface" error does not appear anymore as well. After login on Wayland the task manager is not tracking the new windows and only shows the pinned applications. Occasionally `plasmashell --replace` or `killall plasmashell; kstart plasmashell` fixes the issue but it is very unreliable. I appreciate that the issue is quite unreliable to reproduce so any hints towards more reliable debugging of the issue are welcome. X11 sessions work as expected.
Created attachment 170730 [details] Task manager not showing active window Currently there is 4 windows active (Firefox, Konsole, System setting - About, Spectacle)
I have the same issue on KDE 6 / Manjaro. KDE Plasma version: 6.0.5 KDE Framework Version: 6.2.0 QT version: 6.7.1 Manjaro 24.0.2 The problem often happens after I wake up the computer from sleep. Login-out and back in doesn't solve the issue. Using `plasmashell --replace` neither. But it's gone after a reboot.
Created attachment 170731 [details] plasma logs journalctl -r -S "2024-06-21 09:00:00" | grep "plasma" > logs.txt
Created attachment 171339 [details] current environment I appreciate this is not very helpful but problem still persists with 6.1 (nvidia 555) with no obvious way to debug. Task manager is essentially non functional under Wayland. I am attaching my current environment in case it's useful.
If I may add, I still have this issue from time to time on KDE 6.1.5, and with Intel graphics on Wayland (no NVIDIA involved). Hardware specs: Mesa Intel® Graphics - Intel Corporation Raptor Lake-P [UHD Graphics] (rev 04) - 00:02.0 Kernel: 6.10.13-3-MANJARO
Just to add one more case, I have the same bug described here. Plasma version 6.2.3, KDE Frameworks 6.8.0, QT 6.8.0, kernel 6.11.6, running on Wayland on NixOS 25.05. GPU is Intel UHD 730. I don't see any error messages in the logs; restarting Plasma has no effect; logging in or out has no effect; torching .config and .local has no effect; and the problem presents constantly. I do not experience a freeze of the panel. Happy to provide any logs or diagnostics upon request.
My experience with this problem leads me to believe that there is a probable relation with hardware, at least in my case, so maybe something at a lower level (Wayland?). My observations in several systems and installations: - No problem in Fedora 40 with a 5800X3D/GTX1080Ti. - Problem appeared by moving the SSD from the previous system to a 4700S/RX550. - Problem persisted in a fresh install of Fedora 41 in the same hardware (4700S/RX550). - No problem in a fresh install of Fedora 41 in a 3600X/W5700.
After a bit more experimentation, I can contribute this: 1. The icons-and-text Task Manager displays exactly the same behaviour. 2. The Window List task manager displays a button on the panel to click on, but does not display any open window when you click on it. I'd hypothesise that there's something going on that makes running applications invisible to the Task Managers. One can still Alt-Tab through running applications and they're displayed during the Alt-Tab process, but Task Managers can't see them. Is there some common code that all Task Managers rely upon to see running applications? If anyone knows the name of the correct plasmoid, perhaps I can try some debugging in plasmawindowed to see what's going on.
Yet information for homing in: I switched NixOS channels from "unstable" to "24.11" and the problem has completely disappeared; all the Task Managers are working exactly as expected again. I am still running Wayland, still the same kernel, still the same Plasma, KDE Frameworks, and QT version. Still the same hardware. When you switch channels (without making any other configuration file changes), no user data is affected; .config and .local and so on stay exactly the same. However, the set of applications that you have available to you, and the (sandboxed) system-level installs of those applications, changes. This leads me to think that there is some mismatch at the level of package installation or system changes or system configuration that is causing this problem. Perhaps that is enough to point developers in the right direction, or at least to remove some red herrings on the trail of this bug.