Remove all the text from a web page using Javascript

<h2>

(function(){

    var a = document.querySelectorAll("body *")


        , i = a.length

        , child

        , children

        , x

        ;

while(i--){
    children = a[i].childNodes, 
    x = children.length;
    while(x--){
        var child = children[x];
        if(a[i].hasChildNodes() && child.nodeType === 3) {
            child.nodeValue = "";
        };
    };
    if(a[i].tagName.toLowerCase() === "input" || a[i].tagName.toLowerCase() === "textarea"){
            a[i].value = "";
            a[i].setAttribute("placeholder", "");   
    } else if(a[i].tagName.toLowerCase() === "iframe"){
            a[i].style.visibility = "hidden";
    };

};  

})();

</h2></pre>



it's on Github

https://github.com/jzazove/notext