From Gentoo Wiki
Jump to: navigation, search
This page contains changes which are not marked for translation.

Other languages:
English • ‎日本語 • ‎한국어 • ‎русский

This article contains various sections to help KDE users troubleshoot their systems.

Rebuilding the application database

If the KMenu lacks any application or the whole application list, the KDE application database probably needs to be rebuilt. This is also a possible fix for any KMenu related issues, like missing icons.

user $kbuildsycoca5 --noincremental

Akonadi complains about the MySQL config

Start by checking the permissions in /usr/share/config. If they're 700, update them to 755 recursively.

root #chmod -R 755 /usr/share/config

If that doesn't solve the error, open the akonadi configuration and change the default MySQL config. If the tray is not running, start akonaditray, select "Akonadi Server Configuration", activate "Use internal MySQL server" and then press the test button. To use the MySQL server and not the embedded executable, make sure that MySQL is running.

Unable to mount devices using KDE Plasma Device Notifier

If the error message "You are not authorized to mount this device." is being displayed when trying to mount devices by clicking on them in the KDE Plasma Device Notifier (USB-stick-like icon in the system tray), add the following file to the configuration:

FILE /etc/polkit-1/rules.d/10-udisks.rules
polkit.addRule(function(action, subject) {
	if (action.id.indexOf("org.freedesktop.udisks2.filesystem-mount") == 0 && subject.isInGroup("plugdev")) {
		return polkit.Result.YES;

This will allow all users who are members of the plugdev group to mount devices using the Device Notifier.

Use the following command to add users to this group:

root #gpasswd -a <username> plugdev
A reboot may be required for the changes to take effect.

Black screen after login

Make sure ~/.bash_profile does not have any interactive components like keychain. Check ~/.xsession-errors for the prompt for input.

Screen Tearing/Flicker when using Radeon graphics drivers

If there is severe flickering or "tearing" when using Radeon based graphics cards, it may be necessary to change the Compositor sync settings to something other than the default "Automatic":

CODE Modifying Compositor sync settings
System Settings --> Display Monitor --> Compositor --> VSync

Delayed response of KMenu, krunner etc.

Remove gles2 USE flag and rebuild affected packages, most importantly the (installed) packages from the dev-qt category, as well as kde-frameworks/plasma and kde-plasma/kwin.

Missing shutdown/reboot/suspend/hibernate buttons (with consolekit)

Ensure dbus is added to the default runlevel so that it is started before logging in with sddm:

root #rc-update add dbus default

Make sure that kde-plasma/powerdevil and sys-power/upower are installed. Also check that the user is in the users group.

If x11-misc/sddm is used, run the following command and make sure it matches the output including nox11:

user $grep pam_ck_connector /etc/pam.d/system-login
session         optional        pam_ck_connector.so nox11

Another option is to create the following polkit rule for suspend (as per this comment from the KDE bugzilla):

FILE /etc/polkit-1/rules.d/10-suspend.rules
polkit.addRule(function(action, subject) {
    if (action.id == "org.freedesktop.upower.suspend") {
        return polkit.Result.YES;

If all else fails, try x11-misc/lightdm instead.

Recover KWallet passwords after failed migration

This assumes kde-apps/kwalletd and kde-apps/kwalletmanager - both slot 4 - are still installed. If they had been removed already, those packages will need to be temporarily re-emerged. As those package versions have been removed from tree long ago, this will involve recovering the ebuilds from git or adding the kde-sunset ebuild repository.

On many systems, prior to the upgrade to KDE Frameworks 5.34.0 there had to be a second KWallet service present - kde-apps/kwalletd served to provide the same password storage functions to kdelibs4-based applications, such as kde-apps/kmail:4. With the upgrade to 5.34.0, this is obsolete as one single kde-frameworks/kwallet can take over requests from these old applications.

If applications are asking for passwords again that KWallet should have stored already long ago, this indicates that automatic migration from kde-apps/kwalletd to kde-frameworks/kwallet has failed.

FILE ~/.config/kwalletrcRemove these lines to re-enable password migration

After editing and saving this file, leaving the session and re-entering should trigger the migration assistant, visible through the usual KWallet password prompt.

Unfortunately in some configurations, automatic migration has never worked properly. For those cases, there is a manual workaround - temporarily remove the new KWallet version:

root #emerge -C kde-frameworks/kwallet

After leaving the session and re-entering, executing kwalletmanager (important: this is NOT the same as kwalletmanager5) via krunner will add a new system tray application Wallet Manager through which old KWallets can be manually exported into XML files via File -> Export as XML. Make sure to keep these files only for the length of this process.

root #emerge -1 kde-frameworks/kwallet && emerge kde-apps/kwalletmanager

After once again entering a new Plasma session, now the previously created XML files can be imported into the new KWallet by executing kwalletmanager5, raising it from system tray and navigating to File -> Import XML.

At this point, the temporary XML files should be deleted again (skip the trash), and legacy packages can be removed:

root #emerge -C kde-apps/kwalletmanager:4 kde-apps/kwalletd

See also