Override Cmd+Shift+[ in Chrome?

Question

The goal is to override Cmd+Shift+[ in Chrome.

This question is similar and was considered already, but unfortunately does not help. Cmd+Shift+[ is not a prohibited combination, so it's unclear why it can't be overridden.

The code below overrides Cmd+[, but fails to override Cmd+Shift+[. Instead, the browser default for Chrome occurs instead.

How to override both Cmd+[ and Cmd+Shift+[?

Codepen: https://codepen.io/anon/pen/pXbBZr?editors=1111

function initKeyboardEvents() {
   $(document).keydown(function(event) {

      // Ctrl/Cmd+Shift+[? Move to back.
      if ((event.ctrlKey || event.metaKey) && event.shiftKey && event.keyCode == 219) {
         // Stop browser default.
         event.preventDefault();

         // Push to back.
         alert("push to back");
      }

      // Ctrl/Cmd+[? Move back one layer.
      if ((event.ctrlKey || event.metaKey) && event.keyCode == 219) {
         // Stop browser default.
         event.preventDefault();

         // Push back.
         alert("push back one layer");
      }
   });
}


$(document).ready(function() {
  initKeyboardEvents();

  console.log("document ready");
 });