How to always show children?

Sometimes I notice some children are not showing under a parent, and there is a link saying there are a certain number of “hidden children”. I have to click it, then click on “Add children” (or something) to finally make them show.

How do I disable this? If a parent is expanded, I will always want all of its children to show.

Possibly a bug related to this

Thanks! I created a feature request.