+1  A: 

What is the doctype of the page you are changing?

Also, have you looked at DOM methods?

e.g. document.createElement('B');

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the doctype is text/plainI have not looked into document.createElement(...).
djshaw
From wiki.greasespot.net/Code_snippets: ".innerHTML seems to be sensitive to document.contentType. When the type is text/plain the .innerHTML setter does not parse its argument into DOM nodes, but instead returns #text nodes. The setter seems to work fine for types such as text/html or application/xhtml+xml but where and how it works is undocumented."document.createElement("b") works. Set the text with .textContent = ""
djshaw
var myB = document.createElement('B');myB.appendChild(document.createTextNode('asdfsda'));
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