Message

Avoid Namespace Prefix: foo

Explanation

While XML Namespaces permits the declaration of prefixes for namespaces such as atom and xhtml; to date such declarations haven't proven to be very interoperable in the context of an Atom document.

Here are a few links to prior discussions on the topic:

Solution

Employ the use of default namespaces (i.e., xmlns=) in all Atom and XHTML elements that appear in your feed.

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