Attach (recommended) or Link to PDF file here:
[PATTYP2.pdf](https://github.com/mozilla/pdf.js/files/6471935/PATTYP2.pdf)

Configuration:
- Web browser and its version: FF 88.0.1
- Operating system and its version: W10.0.19042.985
- PDF.js version: https://mozilla.github.io/pdf.js/web/viewer.html

Steps to reproduce the problem:
1. open file to display

What is the expected behavior? (add screenshot)
![grafik](https://user-images.githubusercontent.com/6665575/118114800-5e407800-b3e8-11eb-860f-019f48a8eabf.png)

What went wrong? (add screenshot)
![grafik](https://user-images.githubusercontent.com/6665575/118114841-6c8e9400-b3e8-11eb-8252-1517e5d76475.png)

(memo for me: when fixed, check the files in https://issues.apache.org/jira/browse/PDFBOX-1958 )

return undefined;
      }
      const ctx = this.ctx;
      const fontSizeScale = current.fontSizeScale;
      const charSpacing = current.charSpacing;
      const wordSpacing = current.wordSpacing;
      const fontDirection = current.fontDirection;
      const textHScale = current.textHScale * fontDirection;
      const glyphsLength = glyphs.length;
      const vertical = font.vertical;
      const spacingDir = vertical ? 1 : -1;
      const defaultVMetrics = font.defaultVMetrics;
      const widthAdvanceScale = fontSize * current.fontMatrix[0];
      const simpleFillText =
        current.textRenderingMode === TextRenderingMode.FILL &&
        !font.disableFontFace &&
        !current.patternFill;
      ctx.save();
      let patternTransform;
      if (current.patternFill) {
        
        
        ctx.save();
        const pattern = current.fillColor.getPattern(ctx, this);
        patternTransform = ctx.mozCurrentTransform;
        ctx.restore();
        ctx.fillStyle = pattern;
      }
      ctx.transform.apply(ctx, current.textMatrix);
      ctx.translate(current.x, current.y + current.textRise);