I needed to delete a bunch of One Off cron jobs that we had scheduled but no longer needed. Instead to clicking the checkbox next to each one for 37 pages of results, I wrote up this quick bookmarklet.
javascript:(function(){var f = top.sq_main.document.getElementsByClassName('sq-form-field'); for(var i=0;i<f.length;i++){var type = f[i].getAttribute('type'); var name = f[i].getAttribute('name'); if (type == 'checkbox' && name.indexOf('cron_manager')>-1) {f[i].checked = true;}}})()
Hope this helps someone save some time.