SUMMARY All section names are lowercase, all other KDE packages are in section "kde", plasma-firewall is the only exception. STEPS TO REPRODUCE 1. Update your package list, in case the issue is already fixed 2. Update your package list, bugs get fixed so fast 3. Use apt show plasma-firewall OBSERVED RESULT Section: KDE EXPECTED RESULT Section: kde SOFTWARE/OS VERSIONS Linux: KDE neon User Edition 5.21 KDE Plasma Version: 5.21.0 KDE Frameworks Version: 5.79.0 Qt Version: 5.15.2 ADDITIONAL INFORMATION
This was apparently fixed some time ago, this is all correct in Plasma 6.0.4.