Attach (recommended) or Link to PDF file here:

Configuration:
- Web browser and its version: Chrome 90.0.4430.93
- Operating system and its version: macOs Big Sur 11.2.3
- PDF.js version: 2.7.570
- Is a browser extension: No

Steps to reproduce the problem:
1. Load the attached pdf in https://mozilla.github.io/pdf.js/web/viewer.html
2. Go to page 46. Dotted lines are missing in the graphics (see screenshot from acrobat reader)

What is the expected behavior? (add screenshot) See the screenshot
[Technical_Guide_UK.pdf](https://github.com/mozilla/pdf.js/files/6413001/Technical_Guide_UK.pdf)
![Screenshot 2021-05-03 at 07 46 09](https://user-images.githubusercontent.com/3785784/116844541-a343fd80-abe3-11eb-94c3-d03b3dfd6769.png)

}
      coords.push(p % width1);
      coords.push((p / width1) | 0);
      if (!points[p]) {
        --count;
      }
    } while (p0 !== p);
    outlines.push(coords);
    --i;
  }
  const drawOutline = function (c) {
    c.save();
    
    c.scale(1 / width, -1 / height);
    c.translate(0, -height);
    c.beginPath();
    for (let k = 0, kk = outlines.length; k < kk; k++) {
      const o = outlines[k];
      c.moveTo(o[0], o[1]);
      for (let l = 2, ll = o.length; l < ll; l += 2) {
        c.lineTo(o[l], o[l + 1]);
      }
    }
    c.fill();
    c.beginPath();
    c.restore();
  };
  return drawOutline;
}
class CanvasExtraState {