Two weeks ago, all icons in the KDE 5 apps disappeared. The KDE apps still ran fine, but no icons were shown.
After a while, I found out that I had to do 2 things to get the icons back:
- 1) I had to install kde-frameworks/frameworkintegration
2) I had to set the environment variable XDG_CURRENT_DESKTOP="kde" before starting a KDE app
For KDE Frameworks 5.23 (and probably later), these rules must be changed to:
- 1) kde-frameworks/frameworkintegration must be installed
2) The environment variable XDG_CURRENT_DESKTOP must be set to "XFCE" before starting a KDE app


