I have a polygon featureclass created in ArcGISPro, and I use the Edit -> Merge to join the polygons together which works fine.
I have an external polygon featureclass, imported from Kml (I believe), where if I try the same operation, it does the merge but the shapes disappear. On opening the attribute table, the shape lenght and area are zero. Comparing the two FCs, I see the Z values missing in this imported FC.
Is this a known bug? Is there a quick fix without workarounds
