Hmm, I don’t want to proclaim victory too soon, but maybe it’s largely fixed for me. Your post reminded me to try again:
- I turned on the offline mode and at first was appalled by nearly all covers disappearing, much more than usual.
- Turned offline mode off again and the covers were still gone!
- Scrolled through the whole list, which seems to have triggered a re-caching.
- Turned offline mode back on and all covers seem to be there. However, most are low-res in the album page and small on Now Playing. However, some are fine - no idea what the difference is.
Looks like progress at least. Let’s see if it stays that way.
Edit: Next try two hours later, and the covers are not only still there but those low-res ones I had seen earlier are hi-res now, at least in Now Playing. Though others that I checked now for the first time are still low-res, but it seems I can hope that they will fix themselves as time goes on.
If it continues like this, I’ll consider it largely fixed for me. I hope you have the same experience.
Though it’s possible that there is an issue remaining in so far as many covers show in low-res in the album view when offline, but when I start playing them (while still offline) they are hi-res on Now Playing, so the hi-res version seems to be available and should be used in the album view.
Edit after 13 hours: Still working, except the low-res issue. Not sure about the details of this because some are still low-res in album view but show high in Now Playing, while others stay low in Now Playing, but do switch to high if I load them while online (and then stay high after going offline).