Attach (recommended) or Link to PDF file here:
https://s3.eu-west-1.amazonaws.com/scai-dev.website.com/tmp/8ab8b56a-fa91-11eb-8d74-0242ac110004.pdf

Hi,
Please see an incorrect canvas rendering for the following document - page 9 specifically. It reproduces on https://mozilla.github.io/pdf.js/web/viewer.html (tried with Chrome). Other pages in this document look pretty much the same but the problem is on page 9 only.

Original screenshot:
![image](https://user-images.githubusercontent.com/23075641/129066656-7bb2fb56-2b88-4f40-8e67-b95bdeb9e521.png)


PDF JS:

![image](https://user-images.githubusercontent.com/23075641/129066734-56503a5c-413c-49c1-9e1c-470da3a642ed.png)

const activeSMask = this.current.activeSMask;
    const drawnWidth = activeSMask.canvas.width;
    const drawnHeight = activeSMask.canvas.height;
    const cacheId = "smaskGroupAt" + this.groupLevel;
    const scratchCanvas = this.cachedCanvases.getCanvas(
      cacheId,
      drawnWidth,
      drawnHeight,
      true
    );
    const currentCtx = this.ctx;
    const currentTransform = currentCtx.mozCurrentTransform;
    this.ctx.save();
    const groupCtx = scratchCanvas.context;
    groupCtx.scale(1 / activeSMask.scaleX, 1 / activeSMask.scaleY);
    groupCtx.translate(-activeSMask.offsetX, -activeSMask.offsetY);
    groupCtx.transform.apply(groupCtx, currentTransform);
    activeSMask.startTransformInverse = groupCtx.mozCurrentTransformInverse;
    copyCtxState(currentCtx, groupCtx);
    this.ctx = groupCtx;
    this.setGState([
      ["BM", "source-over"],
      ["ca", 1],
      ["CA", 1],
    ]);
    this.groupStack.push(currentCtx);
    this.groupLevel++;
  }
  suspendSMaskGroup() {