Repro Steps:

1) Create a Page
2) Introduce a Grid Element to the RootGrid and give it a unique name.
3) Navigate to the InteractivityTriggers Panel, target the Grid created and named in Step 2), and apply a DataTrigger to it.
4) Navigate to the DataTrigger's Properties, hover over the 'Binding' row, click on its 3-Dot Menu, and select 'Create Binding'.
5) Navigate to the Bindings 'Name' tab, and under ''ElementName, find, and select the Grid created and named in Step 2).
6) Expand the 'Path' Menu to pick a Path to target.

Observe how the Path listing is empty.

Expected results: The Binding Path listing is available in all circumstances where Paths are available to be targeted.