Attach (recommended) or Link to PDF file here:
[backgroundimage_not_visible_anonymisiert.pdf](https://github.com/mozilla/pdf.js/files/6544725/backgroundimage_not_visible_anonymisiert.pdf)


Configuration:
- Web browser and its version: Chrome Version 90.0.4430.212 (Offizieller Build) (x86_64)
- Operating system and its version: Windows 10, MacOs BigSur
- PDF.js version: 2.5.207
- Is a browser extension: no

Steps to reproduce the problem:
1. open the document in demo viewer.js
2.

What is the expected behavior? (add screenshot)
The backgroundimage gets rendered like in Acrobat Reader
<img width="1348" alt="Bildschirmfoto 2021-05-26 um 09 44 21" src="https://user-images.githubusercontent.com/1286150/119621970-00a82480-be07-11eb-8fed-f74ac04b840b.png">

What went wrong? (add screenshot)
Backgroundimage is not rendered only some  text
<img width="987" alt="Bildschirmfoto 2021-05-26 um 09 43 57" src="https://user-images.githubusercontent.com/1286150/119621938-fab24380-be06-11eb-92ac-4ecb2c9334b1.png">




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

const BORDER_SIZE = 2;
    const offsetX = Math.floor(this._bounds[0]);
    const offsetY = Math.floor(this._bounds[1]);
    const boundsWidth = Math.ceil(this._bounds[2]) - offsetX;
    const boundsHeight = Math.ceil(this._bounds[3]) - offsetY;
    const width = Math.min(
      Math.ceil(Math.abs(boundsWidth * combinedScale[0] * EXPECTED_SCALE)),
      MAX_PATTERN_SIZE
    );
    const height = Math.min(
      Math.ceil(Math.abs(boundsHeight * combinedScale[1] * EXPECTED_SCALE)),
      MAX_PATTERN_SIZE
    );
    const scaleX = boundsWidth / width;
    const scaleY = boundsHeight / height;
    const context = {
      coords: this._coords,
      colors: this._colors,
      offsetX: -offsetX,
      offsetY: -offsetY,
      scaleX: 1 / scaleX,
      scaleY: 1 / scaleY,
    };
    const paddedWidth = width + BORDER_SIZE * 2;
    const paddedHeight = height + BORDER_SIZE * 2;
    const tmpCanvas = cachedCanvases.getCanvas(
      "mesh",
      paddedWidth,
      paddedHeight,
      false