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 )

const ctx = this.ctx;
      const current = this.current;
      const font = current.font;
      const fontSize = current.fontSize;
      const fontDirection = current.fontDirection;
      const spacingDir = font.vertical ? 1 : -1;
      const charSpacing = current.charSpacing;
      const wordSpacing = current.wordSpacing;
      const textHScale = current.textHScale * fontDirection;
      const fontMatrix = current.fontMatrix || FONT_IDENTITY_MATRIX;
      const glyphsLength = glyphs.length;
      const isTextInvisible =
        current.textRenderingMode === TextRenderingMode.INVISIBLE;
      let i, glyph, width, spacingLength;
      if (isTextInvisible || fontSize === 0) {
        return;
      }
      this._cachedGetSinglePixelWidth = null;
      ctx.save();
      ctx.transform.apply(ctx, current.textMatrix);
      ctx.translate(current.x, current.y);
      ctx.scale(textHScale, fontDirection);
      for (i = 0; i < glyphsLength; ++i) {
        glyph = glyphs[i];