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):

this.current.leading = -leading;
    }
    setFont(fontRefName, size) {
      const fontObj = this.commonObjs.get(fontRefName);
      const current = this.current;
      if (!fontObj) {
        throw new Error(`Can't find font for ${fontRefName}`);
      }
      current.fontMatrix = fontObj.fontMatrix || FONT_IDENTITY_MATRIX;
      
      
      if (current.fontMatrix[0] === 0 || current.fontMatrix[3] === 0) {
        warn("Invalid font matrix for font " + fontRefName);
      }
      
      
      if (size < 0) {
        size = -size;
        current.fontDirection = -1;
      } else {
        current.fontDirection = 1;
      }
      this.current.font = fontObj;
      this.current.fontSize = size;
      if (fontObj.isType3Font) {
        return; 
      }
      const name = fontObj.loadedName || "sans-serif";
      let bold = "normal";
      if (fontObj.black) {