Created attachment 137474 [details] Download Themes Window SUMMARY Theme preview is not loading STEPS TO REPRODUCE 1. Open Global Themes 2. Click on Get New Themes 3. In the list all theme preview icons are empty OBSERVED RESULT EXPECTED RESULT SOFTWARE/OS VERSIONS Windows: macOS: Linux/KDE Plasma: (available in About System) KDE Plasma Version: KDE Frameworks Version: Qt Version: ADDITIONAL INFORMATION
I periodically experience this as well, but have not been able to find any specific reproducible case. See also Bug 431319in Discover.