How to show no line around a masking area?

[dc]

Coordinating with caseworker. Working with a linked arch model that shows a cutout in a casework surface. I don't control the arch model. The cutout is no longer required so I have covered the cutout with a masking region. I want the boundary of the masking region to be not visible. In other words, to "disappear into the woodwork". 

[ralphdenhaan · Accepted solution]

Hi,

Use the <Invisible Lines> Line Style

[dc]

This worked. I edited the region by tab-selecting the rectangle which showed that they were detail lines, which I changed as you suggested. However, that's what I thought I did when I created the region in the first place. I must have omitted a step to make the selection "stick". Thank you for your very quick response!