Blender 2.8 - Invisible objects


I’ve been trying to get the hang of blender 2.8 for the past couple of weeks, but I’ve run into a problem with the collections feature.

It seems that sometimes when I hide a collection then un-hide it, it doesn’t show up again. Oddly enough this only applies to the rendered view and the actual render - the objects do show up in other views.
In rendered view though, I can actually see the objects’ selection outlines when I select them - but the objects themselves seem to be completely grayed out in the exact same tone as the background.

Am I missing something, or is this just a bug? And is there a solution/work-around?
One thing I’ve found to work is duplicating the collection - but obviously I’d prefer to not have to do that every time I need to toggle it’s visibility if possible… :s