Trying to use suppress effect in Pro

Question

During the 2023 ESRI UC Plenary, I saw a great way to use the "suppress effect" and control point editing to cartographically remove a line segment.  
https://mediaspace.esri.com/media/t/1_oshgsnmd?st=6105

However, when I try to employ this effect, I cannot show the suppressed section with a different symbol.  I added a second symbol layer, added the suppress effect, and turned on suppress.  This allows me show the whole line as one symbol and the non-suppressed section as another.   I want to show the suppressed section as one symbol, and only the non-suppressed section as another.  It looks like "invert suppression" would allow me to do this, but the invert suppression toggle doesn't do anything.  Is there a tutorial or blog post to set up this suppress effect like presented at the UC?

HaoWong · Answer

I am using Arcgis Pro Sdk 3.0. How to convert vertex to control point and suppress segment s in a line with C# programming？

By the way, when right click the vertex with Pro 3.0, there is no option to convert vertex to control point.

LaurentP · Answer

If you've created the symbology as you've said, then the next step is to add your control points to the line to activate the effect. It's immediate once you deselect the feature.

The effect is only applied to the top line in the symbol properties pane.

My question with regards to this symbology is how the ESRI rep in the video you reference, adds it to her contents list. I see no option to do this except to create a dummy entry in the symbol class list (see attached image). Maybe an enhancement is required here!

Symbol class showing dummy entry.png