Not starting under Gnome, Starting over Terminal brings
Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.
Start it over Terminal with QT_QPA_PLATFORM=wayland amarok brings the same error.
I found this in the Arch Forum: https://bbs.archlinux.org/viewtopic.php?id=268180
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