How can I add xmlns namespace to <html> tag in meteor

This is what I'm trying to accomplish (to integrate Facebook send button using addthis)

<html xmlns:fb="http://ogp.me/ns/fb#">

However the html is out of my control. Meteor also forbids adding attributes to <head> such as:

<head prefix="og: http://ogp.me/ns# fb: http://ogp.me/ns/fb#">

Workarounds that serve the same purpose are more than welcome.

Solution

I'm not sure how to change it through the raw source. But you can use something in your rendered callback to get to it via:

Template.hello.rendered = function() {
    $('html').attr("xmlns:fb","http://ogp.me/ns/fb#");
    $("head").attr("prefix", "og: http://ogp.me/ns# fb: http://ogp.me/ns/fb#");
}

This uses JQuery to modify the html tag as soon as Meteor renders the DOM.