How to Open all external links in a new window

$('a').each(function() {
// The link's href
var theHref = $(this).attr('href').toLowerCase();
// The current domain
var currentDomain = window.location.host;
    // Kill any subdomains
    var noSubDomain = currentDomain.match(/[^\.]*\.[^.]*$/)[0];
    // Create a new (case insensitive) regex from the clean domain
var theDomain = new RegExp(noSubDomain, 'gi');

if(/^https?/gi.test(theHref)) {
// This link is using HTTP/HTTPs and is probably external
if(theDomain.test(theHref)) {
// Do nothing. For some reason, this site is using absolute internal links        
        } else {
$(this).attr('target', '_blank');
}
}
});


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