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Prints item count and total time of current item list in title
// ==UserScript==
// @name Instapaper Reading Time
// @namespace hghwng
// @match *://*.instapaper.com/*
// @grant none
// @description Prints item count and total time of current item list in title
// @version 0.0.1.20180501163143
// ==/UserScript==
(function() {
var items = Array.from(document.querySelectorAll('.meta_read_time.meta_item'));
var minutes = items.map(x => parseInt(x.innerHTML.match(/(\d+) min/)[1]));
var total = minutes.reduce((x, y) => (x + y));
document.title += `: ${items.length} items in ${total} min`;
})();