I refocused onto "anatomical structure", then expanded concepts for that node, allowing all of the nodes to be loaded. Then I clicked undo, then redo. The nodes go to the top right corner, and errors in the console indicate a recursion problem.
http://127.0.0.1:8888/conceptPathToRoot.html?initial_vis=paths_to_root&ontology_acronym=UBERON&full_concept_id=http://purl.obolibrary.org/obo/UBERON_0006590