Given that this keeps dragging on, I'm going to try to implement a workaround, and post here... But not happy about it at all, for the following reasons:
- With a workaround in place, we'll never know if this is ever fixed on Yahoo's side
- At the same time, since this also breaks Apple Mail, the changes are of a fix are pretty good
- I would rather not release Google Play updates without a good test period, and there have been other changes since the release
- There is a reason why my code asks the server for the list of unread messages, not just their count -- to properly handle the unread count for messages that have been moved to the device-only Deleted folder. Not the case with Yahoo, as their server always has a Deleted folder, but it's there in the code as a general mechanism.
