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)

context.fillStyle = ctx.fillStyle;
          context.strokeStyle = ctx.strokeStyle;
          current.fillColor = ctx.fillStyle;
          current.strokeColor = ctx.strokeStyle;
          break;
        case PaintType.UNCOLORED:
          const cssColor = Util.makeHexColor(color[0], color[1], color[2]);
          context.fillStyle = cssColor;
          context.strokeStyle = cssColor;
          
          current.fillColor = cssColor;
          current.strokeColor = cssColor;
          break;
        default:
          throw new FormatError(`Unsupported paint type: ${paintType}`);
      }
    },
    getPattern: function TilingPattern_getPattern(ctx, owner) {
      ctx = this.ctx;
      
      ctx.setTransform.apply(ctx, this.baseTransform);
      ctx.transform.apply(ctx, this.matrix);
      const temporaryPatternCanvas = this.createPatternCanvas(owner);
      return ctx.createPattern(temporaryPatternCanvas, "repeat");
    },
  };
  return TilingPattern;
})();
export { getShadingPatternFromIR, TilingPattern };