Ah ok it wasn’t clear from the original description that it was happening inside the category topic list itself. I had understood it happened on topics in categories on the main topic-list. Screenshots are always useful 
So, the issue happens because the outlet in which the specific ghost replies/view elements are rendered is the topic-list-after-category, which doesn’t appear when there is no category – hence none of the elements appear in that situation.
I’ll have a look to see if we can easily switch that over, but I’m a bit doubtful.