Prevent PageUp and PageDown press in textarea moving website out of the window

index.js

// @see http://www.competa.com/blog/chrome-bug-pageup-pagedown-textarea-moves-website-window/
// @see https://bugs.chromium.org/p/chromium/issues/detail?id=890248
document.querySelector('textarea').addEventListener('keydown', event => {
  if (event.key === 'PageUp' || event.key === 'PageDown') {
    const cursorPosition = event.key === 'PageUp' ? 0 : event.target.textLength;

    event.preventDefault();
    event.target.setSelectionRange(cursorPosition, cursorPosition);
  }
});

I've been annoyed by this for years. It's now 2020 in a few days and the bug is still there. It's even worst when you use white-space="pre", the Home key doesn't even work properly. Personally I will try to avoid hacking anything non-fatal which is supposed to work but doesn't.

Neat, I was wondering if I was the only one seeing such an issue. In my case the PGUP/PGDN keys in a textarea or div[contentEditable] cause an offscreen drawer to appear. What's surprising about the bug is that it survives hard refreshes - the element remains in its erroneous position no matter the number of page refreshes, until I manually close the drawer. I have been looking for a bug report for a few days to no avail.