It appears, that the TIDAL catalogue is dynamic in the sense that not only new albums are added but also old albums are deleted therefrom. If such a TIDAL album which had been added to the ROON library is deleted from the TIDAL catalogue, it apparently disappears also from the ROON library without that the ROON user can notice this. If this album not available any more is important for me, I would perhaps buy a corresponding CD or corresponding flac downloads. It would be very helpful if ROON would keep a log in which all additions and deletions of TIDAL music files would be entered.
Yes, a user facing changelog is a reasonable expectation, one that I requested last fall. But for whatever reason, it did not make it into Roon 1.3. Roon will inform the user of specific files that failed to import – but not of specific files or albums that have been deleted from the local/Tidal library.