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Until CSB5, that EDGE setting only appears in the program window.
It was a great device to help divide pages in the design window especially when the border and the page body are the same color.
CSB 5 finally made those edges publish.
So you can not adjust your settings in the version of the program you have to get the look of the edge.
BUT as with most things, Trellix does allow you to put an IMAGE into the background. You can make an IMAGE that has an edge on it and tile it horizontally and get that look!
Example: Put this image into the background of the top header, set the height of the top to 91 pixels and publish. You have an edge! You can do it in a photo program quite easily, vertically or horizontally!
Been doing it since version 2.1 Trellix! And even though CSB 5 can publish an edge, it is NOT a 3d look like you see in this image. It is a flat line. So this technique still comes in handy!