Just a small function to insert a non-breaking space into a string. And this is what it prevents:

widow example

function widont(heading) {
  let i = heading.lastIndexOf(' ')
  if (i < 0) { return heading }

  let beginning = heading.substr(0, i)
  let end = heading.substr(i + 1, heading.length - i + 1)
  return beginning + '\u00a0' + end
}