Yes, it appears to be still visible when logged out. I did see that the white line only appears in the chrome inspect for certain models – ipad air it disappears, but for ipad mini the line appears. Surface pro 7 it appears also, so I’m not really sure if this is a google chrome error or whether it is really appearing on those devices.
It may be a render issue with those devices splitting a pixel.
Edit that template, select the top most Container Block, and give it a top margin of -1px – does that fix it ?