duplex printing does not work in ubuntu 21.10 within applications like LibreOffice, Firefox or PDF-document viewer. I can select options like double side long edge/short edge, but it always prints single side. It just works with the HPLIP-Toolbox. Obviously the HP Toolbox is using different printer drivers. Somebody an idea how to solve this problem?
During upgrade from ubuntu 21.04 to 21.10 the HPLIP was not upgraded to hplip-3.21.10. After upgrading HPLIP to 3.21.10 everything works fine!
journalctl) for messages around the noted time.