// See original: https://www.labnol.org/internet/highlight-external-links-on-web-pages/9678/
// Highlight External Links by Amit Agarwal
// Published on 06/09/2012

// Find the domain name of the current page
var host = window.location.host;

// Use Google's Favicon Generator
var goog = "http://www.google.com/s2/favicons?domain=";

// Find all hyperlinks on a web page
var links = document.getElementsByTagName("a");

for (i=0; i<links.length; i++) {

  var link = links[i];

  // Skip all internal links where the href is the same as the domain host
  // Also skip non HTTP links like FTP, MAILTO, etc.

  if(link.href.match("^https?://") && !link.href.match(host)) {

    var domain = link.href.split("/");

    // Apply some CSS styles to the external hyperlinks
    link.style.background = "yellow url(" + goog + domain[2] + ") center left no-repeat";

    link.style.fontWeight = "bold";

    link.style.fontSize = "105%";

    link.style.padding="5px 5px 5px 20px";    

    link.style.textDecoration="underline";

  }   
}