PDF.js displays blurry plots in PDF documents, e.g.

http://arxiv.org/pdf/1202.5344v1.pdf

When viewed in Chrome or Adobe Acrobat all the plots show sharp-edged squares. When viewed in Preview or PDF.js, all the squares show as blurry pixelated blobs.

imgData,
      scaleX,
      skewX = 0,
      skewY = 0,
      scaleY,
      positions
    ) {
      if (!this.contentVisible) {
        return;
      }
      const width = imgData.width;
      const height = imgData.height;
      const fillColor = this.current.fillColor;
      const isPatternFill = this.current.patternFill;
      const maskCanvas = this.cachedCanvases.getCanvas(
        "maskCanvas",
        width,
        height
      );
      const maskCtx = maskCanvas.context;
      maskCtx.save();
      putBinaryImageMask(maskCtx, imgData);
      maskCtx.globalCompositeOperation = "source-in";