1. Download the repo as zip and unpack.

2. Go to `chrome://extensions`, toggle `Developer Mode` in the upper right corner and click on `Load unpacked`.

3. Pick the folder from step one and you're good to go.

On any site, you can then click the extension button and text gets "converted", i.e. the first half of a word is bolded (="bionic reading"). The "algorithm" in this extension is:

  const length = word.length;
  const midPoint = Math.round(length / 2);
  const firstHalf = word.slice(0, midPoint);
  const secondHalf = word.slice(midPoint);
  const htmlWord = `<b>${firstHalf}</b>${secondHalf}`;
  return htmlWord;

Further discussion from a couple of weeks ago: https://news.ycombinator.com/item?id=30787290