How to modify the joint between a newel post and stringboard. As usual with the link parameters, you can modify all instances of this joint in your stair, or select and modify a single instance.
You can add a penetration of the string into the newel or have it meet the newel with no penetration.
Once a penetration has been set, you can further adjust the joint by adding an upper, lower and lateral recess (or cut out).
If you add all three, you achieve a mortise and tenon connection.