Attach (recommended) or Link to PDF file here: [A3_Quer.pdf](https://github.com/mozilla/pdf.js/files/7373152/A3_Quer.pdf)


**Configuration:**

- Web browser and its version: Firefox 93.0
- Operating system and its version: macOS 11.6
- PDF.js version: 2.5.207
- Is a browser extension: no

**Steps to reproduce the problem:**
1. Open the attached file in Firefox

We discovered this issue in on older version of this library, but it can be reproduced in the current version of Firefox.

**What is the expected behavior? (add screenshot)**
The file should be rendered with a linear gradient as a background:
![Bildschirmfoto 2021-10-19 um 14 34 00](https://user-images.githubusercontent.com/8649002/137910027-07947e34-700b-4692-b225-d38c36da0d37.png)


**What went wrong? (add screenshot)**
The file is rendered without any background:
![Bildschirmfoto 2021-10-19 um 14 35 05](https://user-images.githubusercontent.com/8649002/137910215-a6b8fb9e-ff95-49f0-93b4-c9f127bd49c1.png)



**Link to a viewer (if hosted on a site other than mozilla.github.io/pdf.js or as Firefox/Chrome extension):**
none
x += coords[pi[q]][0] * m;
            y += coords[pi[q]][1] * m;
          }
        }
        figureCoords[k] = coords.length;
        coords.push([x, y]);
        figureColors[k] = colors.length;
        const newColor = new Uint8Array(3);
        newColor[0] = ((cl[0] * (splitXBy - col) + cr[0] * col) / splitXBy) | 0;
        newColor[1] = ((cl[1] * (splitXBy - col) + cr[1] * col) / splitXBy) | 0;
        newColor[2] = ((cl[2] * (splitXBy - col) + cr[2] * col) / splitXBy) | 0;
        colors.push(newColor);
      }
    }
    figureCoords[0] = pi[0];
    figureColors[0] = ci[0];
    figureCoords[splitXBy] = pi[3];
    figureColors[splitXBy] = ci[1];
    figureCoords[verticesPerRow * splitYBy] = pi[12];
    figureColors[verticesPerRow * splitYBy] = ci[2];
    figureCoords[verticesPerRow * splitYBy + splitXBy] = pi[15];
    figureColors[verticesPerRow * splitYBy + splitXBy] = ci[3];
    this.figures[index] = {
      type: "lattice",
      coords: figureCoords,
      colors: figureColors,
      verticesPerRow,
    };
  }
  _updateBounds() {