Recently I started noticing that a lot of posts will mark as read for a second then go back to unread when viewing just the image or article. It’s not all posts though and I haven’t determined a pattern yet, but opening the comments seems to mark as read on refresh even though the post looks unread before refreshing.
I’m on version 122 of Sync on Android.
The API updated with Lemmy 0.19.4. The old way has been marked for deletion and they’ve now followed through on that, but a few apps (presumably including Sync) haven’t updated to the new way yet
https://lemm.ee/comment/12479585