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.imageLayer.appendImage({
          imgData,
          left: position[0],
          top: position[1],
          width: width / currentTransform[0],
          height: height / currentTransform[3],
        });
      }
      this.restore();
    }
    paintInlineImageXObjectGroup(imgData, map) {
      if (!this.contentVisible) {
        return;
      }
      const ctx = this.ctx;
      const w = imgData.width;
      const h = imgData.height;
      const tmpCanvas = this.cachedCanvases.getCanvas("inlineImage", w, h);
      const tmpCtx = tmpCanvas.context;
      putBinaryImageData(tmpCtx, imgData, this.current.transferMaps);
      for (let i = 0, ii = map.length; i < ii; i++) {
        const entry = map[i];
        ctx.save();
        ctx.transform.apply(ctx, entry.transform);
        ctx.scale(1, -1);
        ctx.drawImage(
          tmpCanvas.canvas,
          entry.x,
          entry.y,
          entry.w,