Add button "Copy task name" to JIRA (version for suxx new JIRA interface)

jira-copy-task.js

// ==UserScript==
// @name         Copy jira task name
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  try to take over the world!
// @author       You
// @match        https://kafoodle.atlassian.net/browse/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    window.addEventListener("load", function(){
        setTimeout(function(){
        var i = document.querySelectorAll('[name="ajs-issuekey"]').item(0).getAttribute('content');
        const copyToClipboard = str => {
            const el = document.createElement('textarea');
            el.value = str;
            el.setAttribute('readonly', '');
            el.style.position = 'absolute';
            el.style.left = '-9999px';
            document.body.appendChild(el);
            el.select();
            document.execCommand('copy');
            document.body.removeChild(el);
        };

        const copyTaskName = () => {
            var d = document.querySelectorAll('#jira-frontend h1').item(0).innerText;
            var desc = i + " " + d;
            copyToClipboard(desc);
        };

        var btn = document.createElement("button");
        btn.onclick = copyTaskName;
        btn.innerText = "Copy task name";
        btn.style = "margin-left: 10px;";
        document.evaluate('//span[text()="' + i + '"]', document, null, XPathResult.ORDERED_NODE_SNAPSHOT_TYPE).snapshotItem(0).parentElement.parentElement.parentElement.append(btn);
    }, 1000);
    });

})();