SUMMARY KDE neon seems to retain every kernel ever installed onto the system, it has gotten to the point where if an issue arises in an update or broken package, i need to wait 30+ minutes just so that update-initramfs generates for ALL KERNELS! In other Ubuntu based distributions Kernels are marked so that autoremove would clean them, but on KDE neon either from discover or the pkcon cli marks all installed kernels as manual making KDE neon retain so many kernel versions when KDE neon should reasonably only have 3-5 (at least for desktop users as this project seems to be aimed at). The only way to fix this as of currently is to manually mark all installed Linux kernels for autoremove.
Thank you for your bug report! However this bug report was created/provided previous to 01/01/2023 and also has not received any updates since before 01/01/2025. Unfortunately KDE neon no longer provides updates for anything older than noble 24.04 based edition's. Please upgrade to KDE neon noble and if you can reproduce the issue after upgrading to an active version, feel free to re-open this bug report. Thanks for understanding!