Duplicate playlists shown from Music (Apple) after upgrade to macOS 10.15.7 (Catalina)

Today I updated my Mac to Catalina 10.15.7 and a test iTunes library along with it.
I launched djayPro 2.2.8 on this upgraded Mac and it showed duplicate (converted) playlists from Music (former iTunes).
To be precise: A playlist-folder “HITS” containing several playlists is shown in djayPro 4 times as playlist folders, each containing different (!) playlists. In Music (former iTunes) all playlist folders and playlists are shown in the correct form and order. Both before and after upgrading the Mac.
Refresh library in djayPro does not solve this problem, nor does a reboot or restart.
“enable XML” is no longer visible in Music, no longer needed?

All the above was done on a duplicate harddisk for try&error reason: not to lose a working Mac.
So no one got hurt. BUT. What is this and can anyone replicate this?


This might be an issue with iTunes splitting into multiple apps. We’ve had it in the past where the original library got mirrored in the Podcasts app (for example). Are you seeing that in the Podcasts/TV apps?