I woke up to a difference between mobile and mac today again (still running 2.1.35). I decided to check is:due count which normally agrees with my mac, but this time it was 24 higher than my mac. I found those due cards and it looks like those exact cards were “due” but it says (filtered) and I don’t even have any filtered decks. Then in the decks section it says no deck (image below) - upon moving back into the original deck the cards reappear in my due count. Why did this error happen?
This has happened to me once before with just a few cards - when I ran the check database option a few cards were moved into this new deck, when I checked it out they also displayed this [no deck] error
That seems to indicate the cards were in a filtered deck that was deleted. Usually all the cards are returned when the deck is removed, but if you modified the cards more recently on another device, the deck move will not be synced. You can avoid this by always syncing at the start and end of each session.