Talk:KDE

Magic Trick (~/.compose-cache) - does it still work?

It seems information of ~/.compose-cache has been lost?

After a bit of testing, it still seems to work just fine:

ls -lh ~/.compose-cache

                                                                                         
-rw------- 1 archie archie  29K  5 mrt 19:27 l4_030_20fca6bc_0e7768ba
-rw------- 1 archie archie 418K  5 mrt 17:23 l4_030_313cb605_00280cc0

Francoism (talk) 20:59, 5 March 2019 (UTC)

Is there any upstream link for this trick? We need to show user this low level trick is actually useful. -- Fengchao (talk) 08:42, 22 November 2019 (UTC)

No upstream link, but I'm using the following as reference:

https://bugs.freedesktop.org/show_bug.cgi?id=3104

http://kdemonkey.blogspot.com/2008/04/magic-trick.html

Francoism (talk) 13:22, 25 April 2020 (UTC)

qt5ct and kvantum bugs after upgrade

This is personal experience though. The true cause are still unknown, but im sure it happens to other user as well especially they who update this when new KDE hidpi option introduced. Dikasetyaprayogi (talk) 01:14, 26 March 2021 (UTC)

Is there any point in this section now? I remember something like this did happen but I didn't solve it in any of the ways suggested here. (I believe I changed my xorg config.) I don't have kvantum installed and I'm pretty sure I never did. I'm not sure what kt5ct is/was, but it isn't in pacman's repositories now and it doesn't seem to be in AUR either. --cfr (talk) 16:45, 21 August 2022 (UTC)

Nvidia GBM support for version 5.23.2

It seems there will be support for GBM coming with KDE version 5.23.2 and the upcoming Nvidia driver: https://www.phoronix.com/scan.php?page=news_item&px=KDE-Plasma-GBM-NVIDIA-Ready

The merge request mentions that GBM will be used as standard, but users can still force EGLstreams with:

 KWIN_DRM_FORCE_EGL_STREAMS=1

I guess that egl-wayland will also not be necessary anymore.

G3ro (talk) 21:00, 24 October 2021 (UTC)

CLI control

It would be useful to have information about controlling KDE from the command line e.g. kwin. This information is hard to find (or I'm bad at finding it) and often useful. For example

qdbus org.kde.KWin /Compositor suspend

qdbus org.kde.KWin /Compositor resume

--cfr (talk) 02:04, 29 September 2022 (UTC)

In those particular instances, those are just D-Bus interfaces. Perhaps we could elaborate on generalized D-Bus usage on that page, and list some of KDE's D-Bus interfaces here (w/ a source code citation). - CodingKoopa (talk) 00:35, 30 September 2022 (UTC)

I created Special:PermanentLink/772926#Tips for finding and using D-Bus interfaces to give this some more visibility. -- CodingKoopa (talk) 17:12, 16 March 2023 (UTC)

Suggested window decoration related tip/trick

If you add an application menu window decoration, you lose the standard application menu from all affected applications. Removing the decoration does not restore the regular menu. Nor does ctrl+m get it back. Instead, you need to change

 MenuBar=Disabled

to

 MenuBar=Enabled

in all ~/.config/applicationrc configuration files and then start the application(s) afresh. --cfr (talk) 18:54, 8 December 2022 (UTC)

Plasma 6 updates

the `plasma-wayland-session` package on longer exists with the plasma 6 release and closer wayland integration. There are probably other entries in this page that need to be updated too. Jmcb (talk) 12:28, 7 March 2024 (UTC)

It is replaced by 'plasma-workspace' which is required by 'plasma-meta' or 'plasma-desktop'. Manual installation is no longer required. LeChauveCape (talk) 16:28, 7 March 2024 (UTC)

Hardware Acceleration

Today I lost hardware acceleration and KWin fell back to software.

I did not find a GUI way to restore hardware acceleration.

There is a [1]KDE Discussion:

edit ~/.config/kdeglobals and remove:
[QtQuickRendererSettings]
SceneGraphBackend=software

This helped me. Maybe this can be added to the KDE trouble shooting? ChrSt (talk) 20:20, 23 February 2025 (UTC)

Forcing KDE through dGPU on hybrid graphics

I very recently started using Arch and decided to go for KDE Plasma for my desktop. However, desktop animations had very low FPS, and I realized that it was because they were being generated by my laptop's iGPU rather than my (nvidia) dGPU.

All information that I could find about similar issues had either solutions for GNOME or KDE on X11, so they were not relevant for me. Finally, I came across a random reddit post which helped:

The answer was to set the `KWIN_DRM_DEVICES` environment variable in such a way that the nvidia card is first in the list, and then the iGPU. For example by adding a bash file under ~/.config/plasma-workspace/env/ with the following:

export KWIN_DRM_DEVICES=/dev/dri/card0:/dev/dri/card1

I am not an expert on the topic, so I would to discuss this solution first, but I think it could help people if we would document this either on this KDE page, or on the PRIME page. Towa (talk) 13:57, 7 June 2025 (UTC)

Setting DRI_PRIME=1 globally works.

Hanabishi (talk) 14:04, 7 June 2025 (UTC)

That was suggested here for GNOME. Maybe it should then indicate that it's also valid for KDE in that case. Towa (talk) 14:08, 7 June 2025 (UTC)

It works for everything. PRIME is a low-level driver thing, it doesn't care what apply to, from its perspective desktop environment is just another regular application.

But if you want to also mention it here in troubleshooting, why not.

Hanabishi (talk) 14:15, 7 June 2025 (UTC)

General KDE / QT troubleshooting tips

Maybe I'm using the wrong search terms but it seems neither here nor on the QT page there are any information on how to get KDE/QT applications to log to console. Had an issue yesterday with skanpage and regardless of what I tried I couldn't get it to output anything to console - or to journalctl for that matter. From what I found on other websites and the forum QT_LOGGING_TO_CONSOLE=1 APP_LOG_LEVEL=DEBUG skanpage should have provided at least some helpful output but it didn't have any effect. Stikle (talk) 16:15, 29 November 2025 (UTC)

Polonium no longer maintained

https://github.com/zeroxoneafour/polonium/issues/195

The developer of this no longer maintains the repo, and there's a comment from them about the AUR not being "officially supported" by them. Dogbr3ath (talk) 23:37, 11 January 2026 (UTC)

I will add mention of this, but the entry can tentatively stay. The AUR package likely still builds and runs, doesn't break any of the AUR rules, and doesn't run afoul of any trademarks (which is a much rarer case,[2] within the category of "AUR packages that are not officially blessed"). As for the utility of keeping it, it's still a notable mention and could be picked up by a community fork. -- CodingKoopa (talk) 02:51, 12 January 2026 (UTC)

KDE Connect mDNS

Regarding the undo 871653: my understanding of bug #487719 is that:

• we can ignore the comment about the autodetection logic because the fix wasn't out yet, but
• it still doesn't detect systemd-resolved mDNS, which caused a hostname conflict on my very system.

I feel it's still worth mentioning possible conflicts and inform the user workarounds exist. Daniele (talk) 13:33, 20 April 2026 (UTC)

Agreed, it's worth mentioning the conflict with systemd-resolved. But you may need to create a new bug report in KDE's bug tracker, since that one is about Avahi. -- nl6720 (talk) 14:43, 20 April 2026 (UTC)