Show notification about available manual system packages updates
Kernel updates are excluded from Plesk update manager (https://support.plesk.com/hc/en-us/articles/115003708353), however, no notification about available kernel updates is shown under Tools & Settings > System Updates. It is necessary to implement such warnings so that one is aware of available updates and can run these manually via command-line interface.
Thank you for your input. We will consider this functionality in upcoming releases if it is popular. Everyone, please continue voting for this feature if you consider it important.
Plesk Tech Support commented
Plesk also has a button to reboot the server, so theoretically kernel updates installation can be completed without having to use CLI at all.