RSS Feed Error – Duplicate Attribute

I figured out my issue. The following attribute was displaying twice:

xmlns:slash=”https://purl.org/rss/1.0/modules/slash/”

Inside the file: /wp-includes/feed-rss2.php there is a section:

xmlns:slash=”https://purl.org/rss/1.0/modules/slash/”
<?php do_action(‘rss2_ns’); ?>

It appears the function do_action(‘rss2_ns’) also puts in the line above it. So I removed the line above (xmlns:slash=”https://purl.org/rss/1.0/modules/slash/&#8221;) and it appears to work now.

Hope this helps others.

Although your feed looks ok, it does not validate. https://feedvalidator.org/check.cgi?url=http%3a%2f%2fohsheglows.com%2f

There is not an error in the wp-includes/feed-rss2.php or everyone using WP would have the error. You changing that file just masked the real error. Normally one does not want to change core WP files.

I was having this same issue. I tracked it down to a plugin called: Slash Comments which was adding the duplicate attribute in the xml. Deactivating the plugin fixed the issue. It looks like the functionality that the plugin served has been added to the WordPress Core code.