Fixing Filelight Pie Chart Rendering on KDE

Problem

Recently Filelight hasn’t been displaying pie chart visualization. Instead it showed a blank gray background. This makes the program almost unusable. Here we fix it.

Solution

Below you can see how it is rendered:

To fix this we need to set an environment variable for Filelight using KDE Menu Editor. I just learned this tool existed! It’s a handy way to modify application launch parameters without editing desktop files manually.

First, search for “filelight” in the top left of KDE Menu Editor, then add QT_QPA_PLATFORM=xcb to the Environment variables section:

Save the settings using the Save button in the top right.

This variable tells Qt to use the X11 backend for drawing the window instead of wayland.

Result

After applying this change, Filelight’s pie chart renders perfectly: