A polyfill to resurrect the blink tag.

blink.js

// http://www.jwz.org/blog/2013/08/a-light-has-gone-out-on-the-web/

/* full-source version */

;(function(doc, cls) {
    var TAG = 'blink'; // try changing this to 'a' or 'p'
    var TIME = 2000; // total loop time (ms)

    var s = doc.createElement('style');
    s.appendChild(doc.createTextNode('.' + cls + ' { visibility: hidden; }'));
    doc.getElementsByTagName('head')[0].appendChild(s);

    var elems = doc.getElementsByTagName(TAG);
    setInterval(function() {
        for (var i = 0, l = elems.length; i < l; i++) {
            elems[i].classList.add(cls);
        }
        setTimeout(function() {
            for (var i = 0, l = elems.length; i < l; i++) {
                elems[i].classList.remove(cls);
            }
        }, TIME / 4); // three units on + one unit off (per jwz)
    }, TIME);
}(document, 'blinking'));

/* minified bookmarklet */

javascript:(function(a,d){var b=a.createElement("style");b.appendChild(a.createTextNode("."+d+" { visibility: hidden; }"));a.getElementsByTagName("head")[0].appendChild(b);var c=a.getElementsByTagName("blink");setInterval(function(){for(var a=0,b=c.length;a<b;a++)c[a].classList.add(d);setTimeout(function(){for(var a=0,b=c.length;a<b;a++)c[a].classList.remove(d)},500)},2E3)})(document,"blinking");