problem with parametric feed URLs?

Hello, there;

I seem to get differing results depending on the nature of the feed-URL employed.

While the example feed-URL https://feeds.feedburner.com/TechCrunch/ (taken from WP-RSS-Retriever’s plugin-page here at wordpress-org) get processed just fine (albeit slow) by my test installation, feed-URLs like https://liberal.is/rssmix/public.php?op=rss&id=-1028&q=Test&key=7msy8757dd177f1f5e5 don’t seem to be. Opening the latter in a browser shows that the problem isn’t the feed being invalid or having no items to show.

An obvious difference appears to be the “complexity” of the URLs, here; your example being very straightforward vs mine toting a tail of parameters.

Do you see any reason why one should work while the other won’t?

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