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)

}
      }
      ctx.putImageData(chunkImgData, 0, i * FULL_CHUNK_HEIGHT);
    }
  }
  function copyCtxState(sourceCtx, destCtx) {
    const properties = [
      "strokeStyle",
      "fillStyle",
      "fillRule",
      "globalAlpha",
      "lineWidth",
      "lineCap",
      "lineJoin",
      "miterLimit",
      "globalCompositeOperation",
      "font",
    ];
    for (let i = 0, ii = properties.length; i < ii; i++) {
      const property = properties[i];
      if (sourceCtx[property] !== undefined) {
        destCtx[property] = sourceCtx[property];
      }
    }
    if (sourceCtx.setLineDash !== undefined) {
      destCtx.setLineDash(sourceCtx.getLineDash());
      destCtx.lineDashOffset = sourceCtx.lineDashOffset;
    }
  }
  function resetCtxToDefault(ctx) {