foo should not contain HTML unless declared in the type attribute
This element contains escaped HTML, but it has declared itself as "text".
type attribute to declare that this is HTML. For example, this is an invalid title in an Atom feed:
<title>My <b>Bold</b> Title</title>
To make it valid, add the following attribute:
<title type="html">My <b>Bold</b> Title</title>
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