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gist.js

function fixUrls(){
    $('a').each(function () {
        //get the original URL
        var theURL = $(this).attr('href');
        if (theURL.includes('t.umblr.com/redirect?')) {
            //split at the equals sign 
            var one = theURL.split('=');
            //split again at the amperstand
            var two = one[1].split('&')
            //get rif of the URL encoding
            var decodedURL = decodeURIComponent(two[0])
            //put decoded URL in the href attribute
            $(this).attr('href', decodedURL)
        }
    })
}