TamperMonkey userscript providing a boilerplate to open other tools with data form Zendesk, with just a keyboard shortcut.

Zendesk_TamperMonkey_UserScript.js

// ==UserScript==
// @name         Open User's Back-office page
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Open user's back-office page straight from Zendesk!
// @author       Théo Blochet
// @match        https://qonto.zendesk.com/agent/tickets/*
// @grant        none
// ==/UserScript==

window.onload = function() {

function myFunc() {

  var map = {};
  onkeydown = onkeyup = function(e) { // This listens for new keyboard 
      map[e.keyCode] = e.type == 'keydown';

      if (map[17] && map[85]) { // 17 means CTRL -on Mac- and 85 means U. That's CTRL+U.
          var userEmail = document.querySelector('.email').innerText; //Here, capture whatever data you want to pass from Zendesk into the URL of your back-office tool
          let backOfficeUrl= `http://localhost:8000/?email=${userEmail}`; //Replace the URL with you backoffice, and pass whatever variable captured above into the URL
          window.open(backOfficeUrl); // This simply opens the URL in a new tab
          map = {}; // This clears the array of keyboard keys pressed
      }
   }
}
  setTimeout(myFunc, 500);
}