How can outlines/contours be displayed using <model-viewer>?

[k-p-1]

Hi,
I would like to display the outline lines for my 3D objects in model-viewer, as seen in the photo below. How can I achieve this?
I work in Rhino3D and export my files via Blender as a glb file. Is there a setting in Blender that I need to adjust before exporting, or a command in model-viewer?
It would be helpful if I could adjust the line thickness and color as well.
Thanks!

[elalish]

We don't support that, as we only do Physically-Based Rendering. You might be able to do this in three.js, in which case you can fork us to add it.

[george-martinec]

Please add