TinyMCE strips html5 tags

Does someone know how to prevent TinyMCE from stripping my <section> tags?

Thanks.

Heres what I do to get HTML tags to work:

On the server navigate to: core/components/tinymce/templates/script.tpl

You'll see this line: Tiny.config = <?php echo $this->modx->toJSON($this->properties); ?>;

Add this line right after it: Tiny.config.valid_elements = "*(*)";

Hope that helps!