After reading stories and hitting back to get to the all stories view , I expect the stories I’ve read to be un-bolded but they are not. They are still marked unread.
Ah, gotcha! Check out the latest Beta release (that came out yesterday) if you can and see if things are improved at all. Version 4.5.0 went a little bit too far in trying to save battery and doesn’t always immediately re-draw the list of stories quickly enough.