I'm running arcmap 10.4.1 trying to make a simple outline from a polygon shapefile. Should be a piece of cake, but a small part of the polygon extends off past the dataframe at the default projection. When I reproject with a 180° central meridian to get the entire thing in one piece, arcmap creates a vertical line where the polygon crossed the dataframe by adding extra vertices.
I can edit these vertices normally such that the line should disappear, but as soon as I deselect the polygon (before I can even save edits) it adds the extra vertices back in!
Has anyone seen anything like this?