This error is hard to debug because it not always happen. I could not find a detailed/defined enough scenario when it exactly happening. Sometimes an error pops up. (See attached image https://ibin.co/3euMMBIUkeAr.png).
I can't trace the problem but it might be one of the following (at least I suspect it, placed a break-point at these lines and traced back where it came from).
Either a use of Cylinder or Polyline worker stopped at the mentioned break-point. I don't know if it has something to do with it, but at least in my case after creating a cylinder, based one radius, i use EllipseGeometryLibrary.computeEllipsePositions and afterwords I use Cartesian3.unpackArray. From that array creating a Polyline.
(Similar to the following code);
var ellipse2 = Cesium.EllipseGeometryLibrary.computeEllipsePositions({
semiMinorAxis: 300000,
semiMajorAxis: 300000,
rotation: 0,
center: Cesium.Cartesian3.fromDegrees(-100, 34),
granularity: Cesium.Math.RADIANS_PER_DEGREE
}, false, true);
var innerPositions = Cesium.Cartesian3.unpackArray(ellipse2.outerPositions);
Again I am not sure if that is related but I need to find a solution ASAP, and that is the only lead I have.