Message
foo claims to be base64-encoded, but isn't
Explanation
content is expected to be encoded in base64 if the "type" attribute of atom:content is a MIME media type, but is not an XML media type, does not begin with "text/", and does not end with "/xml" or "+xml".
Solution
Encode the content in base64, or reference it indirectly via the
src attribute.
Not clear? Disagree?
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