Filters have been expanded to see Reference Planes.
You're probably aware that Reference Planes don't have many parameters, just these three instance parameters: Scope Box, Name and Subcategory. They don't have any Type Parameters because they aren't defined by types like grids or levels for example. If we examine the Filters dialog and see how those three parameters play out as criteria we'll find they don't.
The More Parameters... or Browse button to its right are tempting but we still can't create parameters associated with Reference Planes.
This makes it rather difficult to actually use a Filter for Reference Planes, criteria based filters anyway. We can select them (Reference Planes) first and create a Filter based on selection but that's not really much different than using Visibility/Graphics to turn them off or override their appearance.
While it makes for an enticing item in the list of what's new it will only serve to frustrate you if you pursue it. It's a shame that we aren't offered at least the Name parameter to use in a filter. It looks like the critical path for this feature wandered into the weeds and got stuck in some quicksand.
I'm sure we'll take good advantage of being able to differentiate them from one another and control their visibility using Visibilty/Graphics and View Templates despite this situation.