Some focus stories will sometimes be missing from the list in All Stories. After viewing the feeds that contain them, they correctly appear in the feeds and in All Stories. Toggling Focus mode off and back on also seems to help. Sliding down in Android to refresh has no effect on the stories, unlike the behavior in this old post.
I’ve primarily experienced this on Android, but in the past also on web. I’ve tried clearing and reinstalling the Android app, and switching from F-Droid to Google Play, but the problem eventually returns with new stories. I noticed that the request to /reader/river_stories
on web includes non-focus stories regardless of the focus slider setting. Perhaps this is a caching/pagination issue that is skipping over a page of stories.