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)

m[1] * c + m[3] * d,
      m[0] * e + m[2] * f + m[4],
      m[1] * e + m[3] * f + m[5],
    ];
    ctx._originalTransform(a, b, c, d, e, f);
  };
  ctx.setTransform = function ctxSetTransform(a, b, c, d, e, f) {
    this._transformMatrix = [a, b, c, d, e, f];
    ctx._originalSetTransform(a, b, c, d, e, f);
  };
  ctx.resetTransform = function ctxResetTransform() {
    this._transformMatrix = [1, 0, 0, 1, 0, 0];
    ctx._originalResetTransform();
  };
  ctx.rotate = function ctxRotate(angle) {
    const cosValue = Math.cos(angle);
    const sinValue = Math.sin(angle);
    const m = this._transformMatrix;
    this._transformMatrix = [
      m[0] * cosValue + m[2] * sinValue,
      m[1] * cosValue + m[3] * sinValue,
      m[0] * -sinValue + m[2] * cosValue,
      m[1] * -sinValue + m[3] * cosValue,
      m[4],
      m[5],
    ];
    this._originalRotate(angle);
  };
}
class CachedCanvases {