// ==UserScript==
// @name         Sort JIRA comments in ascending order (oldest first).
// @namespace    http://stevekehlet.com
// @version      0.2
// @description  Always sort JIRA comments ascending.
// @author       Steve Kehlet
// @match        https://jira.atlassian.com/browse/*
// ... include more match statements here, including your private JIRA repos
// @grant        none
// @downloadURL none
// ==/UserScript==

(function() {
    'use strict';
    $('.issue-activity-sort-link').each(function () {
        var sortLink = $(this);
        // when the link says 'asc', it means it's currently sorted descending
        if (sortLink.attr('data-order') == 'asc') {
            // use .issue-view if there's a sidebar and scrollable frame to the right, otherwise window
            var selector = $('.issue-view').length > 0 ? '.issue-view' : window;
            var scrollPos = $(selector).scrollTop();
            // scroll back to where we were after clicking
            $(selector).one('scroll', function () {
                $(selector).scrollTop(scrollPos);
            });
            sortLink.click();
        }
    });
})();