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sndrs/non-blocking-document.write.html

Created August 27, 2015 12:00
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Override document.write to prevent 3rd parties injecting blocking scripts
Raw
non-blocking-document.write.html
<!DOCTYPE html>
<html>
<head>
<title></title>
<script>
(function(Document) {
Document.prototype.write = function(s) {
var allScripts = document.getElementsByTagName('script'),
thisScript = allScripts[allScripts.length-1];
var writeTarget = document.createElement('div');
writeTarget.innerHTML = s;
window.onload = requestAnimationFrame(function () {
thisScript.parentElement.insertBefore(writeTarget, thisScript);
});
}
})(Document)
</script>
</head>
<body>
<div>div 1</div>
<script>
document.write("between 2 divs")
</script>
<div>div2</div>
</body>
</html>
@mxdvl
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mxdvl commented Sep 30, 2021

This is brilliant!

I’ve forked this for use with document.createElement in https://gist.github.com/mxdvl/bb4042dc1448745c3dc707dc771e0e1b

@topbestcoder
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A mistake :
})(Document) => })(document)

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