Thank you for contacting us.
We do not offer such functionality out of the box. This means you will need to customize your RSS Outbound Pipe in order to achieve this. I can recommend you go through my blog post
. In the code I am adding a custom blog post field to the feed, but the methodology for adding a static value is the same. Simply extend the Syndication item using the method SyndicationItem.ElementExtentions.Add() and pass your value there.
I hope this helps. Feel free to get back to us if you need additional assistance.
Ivan D. Dimitrov
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