Attach (recommended) or Link to PDF file here: [RenderIssue.pdf](https://github.com/mozilla/pdf.js/files/7583657/RenderIssue.pdf)

Configuration:
- Web browser and its version: Chrome Version 96.0.4664.45 (Official Build) (64-bit)
- Operating system and its version: Windows 10 Version 10.0.19042

- PDF.js version: v2.12.201 (If this looks incorrect, please take it from the URL)
- Is a browser extension: No, using https://mozilla.github.io/pdf.js/web/viewer.html

Steps to reproduce the problem:
1. Visit https://mozilla.github.io/pdf.js/web/viewer.html
2. Drop the attached PDF on to the page - [RenderIssue.pdf](https://github.com/mozilla/pdf.js/files/7583657/RenderIssue.pdf)

What is the expected behavior? It should appear as in Adobe Reader - 
![image](https://user-images.githubusercontent.com/94864394/142921185-1ee7034b-1db9-4b6d-ae08-4a9cb4426d70.png)

What went wrong? Some text is blank - 
![image](https://user-images.githubusercontent.com/94864394/142921086-a5ad3ad7-caac-40d8-92d3-684d59aee1f5.png)

Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension): N/A

if (!this.current.activeSMask) {
      return;
    }
    if (!dirtyBox) {
      dirtyBox = [0, 0, this.ctx.canvas.width, this.ctx.canvas.height];
    } else {
      dirtyBox[0] = Math.floor(dirtyBox[0]);
      dirtyBox[1] = Math.floor(dirtyBox[1]);
      dirtyBox[2] = Math.ceil(dirtyBox[2]);
      dirtyBox[3] = Math.ceil(dirtyBox[3]);
    }
    const smask = this.current.activeSMask;
    const suspendedCtx = this.suspendedCtx;
    composeSMask(suspendedCtx, smask, this.ctx, dirtyBox);
    
    
    this.ctx.save();
    this.ctx.setTransform(1, 0, 0, 1, 0, 0);
    this.ctx.clearRect(0, 0, this.ctx.canvas.width, this.ctx.canvas.height);
    this.ctx.restore();
  }
  save() {