Map Overworld - Mouseover "hidden" map popup on non-map nodes.

Hi all, I'm doing maps tonight and have this issue happening where I will mouseover an apparently empty portion of the map and it will show "Reliquary Vault", "Burning Monolith, "Realmgate", etc.

These are on apparently "unreachable" parts of the map that are adjacent to usable nodes. Not sure if these are simply hidden nodes but I did not try to use a map on them.

Haven't seen this behaviour before. Fyi/Thanks.