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.

constructor(IR) {
    super();
    this._coords = IR[2];
    this._colors = IR[3];
    this._figures = IR[4];
    this._bounds = IR[5];
    this._matrix = IR[6];
    this._bbox = IR[7];
    this._background = IR[8];
  }
  _createMeshCanvas(combinedScale, backgroundColor, cachedCanvases) {
    
    
    const EXPECTED_SCALE = 1.1;
    
    const MAX_PATTERN_SIZE = 3000;