I haven't used this application for many years apart from checking that
there's nothing in the calendar. However, I'm still getting reminders of
events that were in the calendar years ago. I assume the zombies are
still in the Akonadi database so how can I get rid of them?

Graham Davis, Bracknell, Berks., UK.
openSUSE Tumbleweed; KDE Plasma 5.11.3; Qt 5.9.2; Kernel 4.13.12;
AMD Athlon X4 860K Processor; Sound: FCH Azalia;
Video: nVidia GeForce 210 (Driver: nouveau)