I have an app which reads lots of RSS feeds.
Someone added a feed recently that includes images in the html portion with relative URLS (i.e. it didn't include the http://www.domain.com/ part in front).
Is this valid html for an RSS feed? I thought not, but I tried adding the feed to my Google reader and it picked up the images correctly, so they must be doing something smart where they guess the domain based on the feed's url parameter or something.
Even if it's not valid, how common is it to see feeds like this in the wild? To display it correctly would require you to parse the html in the feed and find/replace parts of it to insert full URL's, so this seems wrong. But wanted to double check.