Can't loft to/from a Face?

[tve]

I'm using a finder to identify the face of a Shape and I'd to loft from there to a sketch. But I'm failing...
See example
where I'm trying to loft from the red face to the blue circle.

Uncomment line 11 (the loftWith) to see the error I'm getting:

const r = replicad

export default function main(p) {
  const box = r.makeBaseBox(30, 10, 20).translateY(-5)

  const triBase = new r.FaceFinder().inPlane("XZ", 0).find(box, {unique: true})
  const triTop = r.drawCircle(10).
    translate(0, 10). // lay onto XY plane
    sketchOnPlane("XZ", -20)

  //const tri = triTop.loftWith(triBase)

  return [
    { shape: box, name: "sleeve", color: "green" },
    { shape: triTop, name: "tri", color: "blue" },
    { shape: triBase, name: "triBase", color: "red" },
    //{ highlightFace: triBase, color: "red" }, // doesn't do anything!?
  ]
}

[sgenoud]

You need to loft with another sketch, and not a face (which might have hole in it and become more complicated.

You can see how I would do this here

I should add the sketchFace helper method.

Also, you can see how you would highlight a face (but I need to document this properly).