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
cs: dict.getRaw("CS") || dict.getRaw("ColorSpace"),
      xref,
      resources,
      pdfFunctionFactory,
      localColorSpaceCache,
    });
    this.background = dict.has("Background")
      ? cs.getRgb(dict.get("Background"), 0)
      : null;
    const fnObj = dict.getRaw("Function");
    const fn = fnObj ? pdfFunctionFactory.createFromArray(fnObj) : null;
    this.coords = [];
    this.colors = [];
    this.figures = [];
    const decodeContext = {
      bitsPerCoordinate: dict.get("BitsPerCoordinate"),
      bitsPerComponent: dict.get("BitsPerComponent"),
      bitsPerFlag: dict.get("BitsPerFlag"),
      decode: dict.getArray("Decode"),
      colorFn: fn,
      colorSpace: cs,
      numComps: fn ? 1 : cs.numComps,
    };
    const reader = new MeshStreamReader(stream, decodeContext);
    let patchMesh = false;
    switch (this.shadingType) {
      case ShadingType.FREE_FORM_MESH:
        this._decodeType4Shading(reader);
        break;
      case ShadingType.LATTICE_FORM_MESH: