Tampermonkey (https://tampermonkey.net/) script to indicate on BBC iPlayer browser tabs when the episode becomes unavailable.

iplayer_availability_time_on_tabs.user.js

// ==UserScript==
// @name         iPlayer better tabs
// @namespace    http://henrik.nyh.se/
// @version      0.2
// @description  Indicates on browser tabs when the episode becomes unavailable. Counts down if the tab is left open. Also strips title prefixes like "BBC iPlayer" so tabs show actual titles.
// @author       Henrik Nyh
// @match        http://www.bbc.co.uk/iplayer/*
// @match        http://www.bbc.co.uk/programmes/*
// @grant        none
// @updateURL    https://gist.githubusercontent.com/henrik/c7ad3b90379a19f2c0164b3243c6b378/raw
// ==/UserScript==

(function() {
  "use strict";

  var updateEverySeconds = 60;

  // Strip prefixes from title.

  var niceTitle = document.title.replace(/^BBC (iPlayer|One|Two|Three|Four) - /, "");
  document.title = niceTitle;

  // Show countdown, if available.

  var match = document.body.innerHTML.match(/"availabilityEnd":"(.+?)"/);
  if (!match) return;

  var endDate = new Date(match[1]);

  function updateTitle() {
    var now = new Date();
    var msLeft = endDate - now;
    var daysLeft = msLeft / 1000 / 60 / 60 / 24;

    var prefix;
    if (daysLeft < 0)       { prefix = "gone :("; }
    else if (daysLeft < 1)  { prefix = "<1d!"; }
    else if (daysLeft > 31) { prefix = "1m+"; }
    else {
      var fullDays = Math.round(daysLeft);
      prefix = fullDays + "d";
    }

    document.title = "[" + prefix + "] " + niceTitle;
  }

  updateTitle();
  setInterval(updateTitle, 1000 * updateEverySeconds);
})();