// Bookmarklet
javascript:var betterlink;betterlink||function(a,b,c){var d,e=a.getElementsByTagName(b)[0];a.getElementById(c)||(d=a.createElement(b),d.id=c,d.defer=!0,d.src="//code.betterlink.co/betterlink.js",d.setAttribute("data-script-source","bookmarklet"),e.parentNode.insertBefore(d,e))}(document,"script","betterlink-js");
// Bookmarklet
javascript:var betterlink;betterlink||function(a,b,c){var d,e=a.getElementsByTagName(b)[0];a.getElementById(c)||(d=a.createElement(b),d.id=c,d.defer=!0,d.src="//code.betterlink.co/betterlink.js",d.setAttribute("data-script-source","bookmarklet"),e.parentNode.insertBefore(d,e))}(document,"script","betterlink-js");

/*
var betterlink;
if(!betterlink){
  (function(d,s,id){
    var js,fjs = d.getElementsByTagName(s)[0];
    if(!d.getElementById(id)){
    js=d.createElement(s); js.id = id; js.defer = true;
    js.src="//code.betterlink.co/betterlink.js";
    js.setAttribute('data-script-source','bookmarklet');
    fjs.parentNode.insertBefore(js,fjs);}
  }(document,'script','betterlink-js'));
}
*/

comment unminified version of script