https://boersengefluester.de/wp-content/uploads/assets/annuals/2019/578560.pdf

Configuration:
- PDF.js version: 2.7.570

Steps to reproduce the problem:
1. Load the linked PDF
2. On the second page, highlight the word "Mitarbeiterinnen" by double-clicking it

What is the expected behavior?
The word should be recognized as a single word and highlighted as such.

What went wrong?
Instead, it's recognized as 3 words: "Mit", "arbei", "terinnen"
![image](https://user-images.githubusercontent.com/5265630/114384414-f8fe2a80-9b8e-11eb-8843-5099425b0fad.png)

This happens for many words in this PDF.

Is there anything that can be changed in how I use pdfjs-dist to make it recognize this as a single word? Just looking at the PDF, I can't tell what would cause this behavior.

descent = 0;
  for (let i = pixels.length - 1 - 3; i >= 0; i -= 4) {
    if (pixels[i] > 0) {
      descent = Math.ceil(i / 4 / DEFAULT_FONT_SIZE);
      break;
    }
  }
  
  
  
  ctx.clearRect(0, 0, DEFAULT_FONT_SIZE, DEFAULT_FONT_SIZE);
  ctx.strokeText("A", 0, DEFAULT_FONT_SIZE);
  pixels = ctx.getImageData(0, 0, DEFAULT_FONT_SIZE, DEFAULT_FONT_SIZE).data;
  ascent = 0;
  for (let i = 0, ii = pixels.length; i < ii; i += 4) {
    if (pixels[i] > 0) {
      ascent = DEFAULT_FONT_SIZE - Math.floor(i / 4 / DEFAULT_FONT_SIZE);
      break;
    }
  }
  ctx.restore();
  if (ascent) {
    const ratio = ascent / (ascent + descent);
    ascentCache.set(fontFamily, ratio);
    return ratio;
  }
  ascentCache.set(fontFamily, DEFAULT_FONT_ASCENT);
  return DEFAULT_FONT_ASCENT;
}
function appendText(task, geom, styles, ctx) {