* Peter P. <peterparker(a)fastmail.com> [2025-08-20 12:11]:
  Hi, after upgrading qjackctl to 1.0.4 its system tray
icon is no longer
 displayed albeit the program starts. In 2023 this could be solved by
 installing libqt6svg6 but not so today. qjackctl posts in the shell
        QSystemTrayIcon::setVisible: No Icon set
 (How) can I solve this problem?
 Thanks!
 Peter 
Following up to myself here:
After installing a few more icon-related Debian packages trying to fix
the above error, the qjackctl GUI is no longer shown at all (no windows)
but jackd is started and is usable.
cheersz, Peter