How safe is it use document.body.innerHTML.replace?
<p>Is running something like:</p>

<p>document.body.innerHTML = document.body.innerHTML.replace('old value', 'new value') </p>

<p>dangerous?</p>

<p>I'm worried that maybe some browsers might screw up the whole page, and since this is JS code that will be placed on sites out of my control, who might get visited by who knows what browsers I'm a little worried.</p>

<p>My goal is only to look for an occurrence of a string in the whole body and replace it.</p>
