Tampermonkey Jira Rollup Subtask Estimates

// ==UserScript==
// @name         Rollup subtask estimates
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  try to take over the world!
// @author       You
// @match        https://infuerno.atlassian.net/secure/RapidBoard.jspa?*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    // Your code here...
    $(document).ready(function () {
        $('.ghx-issue-content').each(function() {
            let estimate = $(this).find('span.ghx-extra-field-content').text();
            let hoursAndMins = estimate.split(', ');
            let shortHoursAndMins = '-';
            for(let i = 0; i < hoursAndMins.length; i++) {
                let s = /(\d+ (h|m))\S+/.exec(hoursAndMins[i]);
                if (s) {
                    shortHoursAndMins = shortHoursAndMins.replace('-', '') + s[1].replace(' ', '') + ' ';
                }
            }
            shortHoursAndMins = shortHoursAndMins.trim();
            $(this).find('span.ghx-statistic-badge').text(shortHoursAndMins);
            $(this).find('div.ghx-plan-extra-fields').hide();
        });
    });
})();