Reverse text on webpage

reverse.js

(function(body) {

    var text = [], 
        treewalker = document.createTreeWalker(body, NodeFilter.SHOW_TEXT, null, false);
    
    while(treewalker.nextNode()) {   
        if (treewalker.currentNode.nodeValue.charAt(0) !== '\n') {
            text.push(treewalker.currentNode);
        }     
    };

    text.forEach( function(txt) {
        txt.nodeValue = txt.nodeValue.split(' ').map(function(word) {

            var firstLetterUppercase = word.substr(0,1) === word.substr(0,1).toUpperCase();
            var segments = word.match(/([\W]+)?([\wÆØÅæøå]+)?([\W]+)?/);

            if (segments[2]) {
                segments[2] = segments[2].toLowerCase().split("").reverse().join("");
                if (firstLetterUppercase) {
                    segments[2] = segments[2].charAt(0).toUpperCase() + segments[2].slice(1);
                }
            }

            return (segments[1] || '') + (segments[2] || '') + (segments[3] || '');

        }).join(' ');
    })

}(document.body))