How to show missing edges with Freestyle edge mode? Are there any settings to make edge marks appear at all angles when rendered? I edge marked part of Suzanne's head but when certain angles are rendered parts of the edge marks are invisible.

For example:


Edge Marks working ok at certain angles



Edge Marks are invisible at certain angles
Yes.

The edge disappears because it is no longer visible. This is more obvious on a shaded model:



If you want freestyle edges to be visible at all times, disable selection by visibility: