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)

entry.h,
          0,
          -1,
          1,
          1
        );
        if (this.imageLayer) {
          const position = this.getCanvasPosition(entry.x, entry.y);
          this.imageLayer.appendImage({
            imgData,
            left: position[0],
            top: position[1],
            width: w,
            height: h,
          });
        }
        ctx.restore();
      }
    }
    paintSolidColorImageMask() {
      if (!this.contentVisible) {
        return;
      }
      this.ctx.fillRect(0, 0, 1, 1);
    }
    
    markPoint(tag) {
      
    }
    markPointProps(tag, properties) {