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)

this.setLineWidth(value);
            break;
          case "LC":
            this.setLineCap(value);
            break;
          case "LJ":
            this.setLineJoin(value);
            break;
          case "ML":
            this.setMiterLimit(value);
            break;
          case "D":
            this.setDash(value[0], value[1]);
            break;
          case "RI":
            this.setRenderingIntent(value);
            break;
          case "FL":
            this.setFlatness(value);
            break;
          case "Font":
            this.setFont(value[0], value[1]);
            break;
          case "CA":
            this.current.strokeAlpha = state[1];
            break;
          case "ca":
            this.current.fillAlpha = state[1];
            this.ctx.globalAlpha = state[1];
            break;