In our forum we’re running RSS Polling (right now it’s 69bbeae. This issue happened ~15 days ago). The issue is that links with diacritics (e.g. ó or à) instead of getting the actual original URL, they domain part of the URL gets the forum’s.
If you look at this post you’ll find it fixed, but in the edit history, you can see that the links were previously broken.
Wow tricky one, going to put a pr-welcome for now.
Are you sure the origin is shipping with the correct encoding flags in the HTTP payload?
My hypothesis as to why this could be an issue on discourse has to do with the fact that both are relative URLs, but one is processed correctly and another one isn’t. My assumption (which could be wrong) is that the RSS plugin should always link to the part website correctly in relative URLs regardless of encoding.