How to Customize the Lock Screen on KDE

There’s a popular saying that “if there’s something about KDE you don’t like, there’s probably a button that lets you change it“, and the default lock screen might be one of the things you’d like to change. Whether you’re an Android, Windows or Mac OS X user, you’re probably familiar with the lock screen feature. It’s a simple and quick way to protect your computer from unauthorized access while you’re temporarily away from the keyboard.

KDE offers three types of lock screen: simple locker, Desktop Widgets, and screensaver. The System Settings dialog lets you perform basic customization, but there are tricks and tweaks that can be achieved by modifying configuration files. This guide is based on KDE 4.13.2, so your settings might look very different if you’re using a KDE version older than 4.10.


You can access the KDE lock screen feature either from the right-click menu on your desktop, from the Plasma Toolbox on the desktop (by clicking the “cashew” icon), or by pressing the designated keyboard shortcut. The settings dialog can be found in “System Settings -> Display and Monitor -> Screen Locker”. Here you can select the type of lock screen you want to use.


By default, simple locker’s background is either a blank screen or the default wallpaper of your current Plasma theme. It doesn’t allow for any changes, as the developers probably assumed that users wouldn’t need to modify it. However, the fact that they reported this missing feature as a bug indicates the opposite. Still, you can customize the background and the greeting message of your simple locker by editing a few files.

To change the background, find an image you would like to use, give it a simple name (for example, “locked.jpg”) and place it in the directory as stated below. Note that this requires root privileges, and this change will be visible to all users of the system.

sudo mv /home/$USERNAME/Desktop/locked.jpg /usr/share/kde4/apps/ksmserver/screenlocker/org.kde.passworddialog/contents/ui

Now open the configuration file with your preferred text editor,

sudo leafpad /usr/share/kde4/apps/ksmserver/screenlocker/org.kde.passworddialog/contents/ui/main.qml

and find the line beginning with Image {. Edit the part after source: by replacing theme.wallpaperPathForSize(parent.width, parent.height) with the name of the image you previously copied. Make sure to enclose the filename in quotation marks like this: “locked.jpg.” Save the changes and the result will be visible the next time you lock your screen.


To add a custom login message, open the following file,

sudo leafpad /usr/share/kde4/apps/ksmserver/screenlocker/org.kde.passworddialog/contents/ui/Greeter.qml

and find the line containing PlasmaComponents.Label.


Insert your message in quotation marks after text: and save changes.


It’s important to remember that these changes will be overwritten when you update the package kdebase-workspace; that is, when you upgrade to a new KDE version.

This type of lock screen functions much like the Plasma Widget Dashboard – it’s a blank space on which you can add widgets (plasmoids) like clocks, a calendar or sticky notes. To add widgets, click the “Configure” button next to Desktop Widgets in “System Settings -> Display and Monitor -> Screen Locker”. You’ll be transferred to editing mode, where you can select actions from the “cashew” menu in the corner.


Choosing “Settings” opens a dialog where you can configure the background. It can be a static image, an animation, a slideshow …


The “Add Widgets” option activates a toolbar from which you can drag widgets onto the lock screen. For security reasons, the selection of available widgets is very limited, and due to a bug, they can’t be resized by drag-and-drop like on the Plasma Dashboard. However, you can change their size in the configuration file.


First add the widgets you want to use, and exit the editing mode by clicking “Leave Screensaver” in the cashew menu. Then open the file:


(Depending on your distribution, you might have to replace “.kde” with “.kde4” in the path above.)

Every widget has a “geometry” property with four numbers determining its size and position. The first number is the horizontal offset from the top left corner, the second is the vertical offset, and the last two numbers are the width and height of the widget, respectively. All you have to do is modify these values for the widget you wish to resize and save the changes.

KDE offers several types of screensavers, some of which can be customized by clicking the “Setup” button. You can install additional screensavers from the repositories of your distribution.


If you want the screensaver to activate after a certain amount of time, tick the “Start automatically after” box. In case your screensaver doesn’t start, check the “System Settings -> Desktop Effects -> Advanced” dialog and make sure the “Suspend desktop effects for fullscreen windows” option is disabled.

It’s possible to disable the lock screen on KDE. You can open the /home/$USERNAME/.kde/share/config/kscreensaverrc file and add:


Afterwards, check the following settings:

  • in “System Settings -> Display and Monitors -> Screen Locker.” “Start automatically after” should be disabled.
  • in “System Settings -> Power Management -> Energy Saving.” None of the options should have “Lock screen” selected.
  • in “System Settings -> Power Management -> Advanced Settings.” “Lock screen on resume” should be disabled.

The latest KDE version, Plasma 5, is still not as widely used as the 4.1x series, and its lock screen component has been completely redesigned. It no longer supports the screensaver or the Desktop Widgets mode, leaving only the simple option with rudimentary settings.


Have you tried Plasma 5? If you have any customization tips for the new KDE lock screen, please share them in the comments below.

Image credit: Teaser image source, Featured image source