When I run DRC I get a track error for an 'invisible track'. I can't see it or delete it. It's also there when I export a PDF, but not visible in the editor.
Update: going through net by net, suddenly it appeared and I was able to select and delete it. Odd!
Brand new interactions and interfaces. 
Easy to use and quick to get started. 
Hi
If you deselect it at design manager, you won't show up in the canvas.